RESUMO
Two endophytic bacterial strains, designated S1-1-2 T and S1-1-8, were isolated from the leaves of a mangrove plant, Avicennia marina. The isolates were Gram-stain-negative, motile, rod-shaped bacteria with lateral flagella. Growth occurred at 4-41 °C, pH 4.0-11.0, and 0.5-25.0% NaCl. The predominant fatty acids of the novel strains were C18:1 ω6c/ω7c, C19:0 cyclo ω8c, and C16:0. The predominant respiratory quinone was Q-9. The DNA G + C contents of strains S1-1-2 T and S1-1-8 analyzed by genome sequences were 63.8%. Phylogenetic analysis based on 16S rRNA gene sequences obtained using sanger sequencing and whole-genome phylogenetic analysis revealed an affiliation between the two strains and the genus Salinicola in the class Gammaproteobacteria. Detailed genotypic, chemotaxonomic, and phenotypic data support the conclusion that these two strains should be described as a novel species in the genus Salinicola. Here, Salinicola avicenniae sp. nov. (type strain S1-1-2 T = LMG 32655 T = MCCC 1A19027T) is proposed.
Assuntos
Avicennia , Composição de Bases , DNA Bacteriano , Gammaproteobacteria , Filogenia , RNA Ribossômico 16S , Avicennia/microbiologia , RNA Ribossômico 16S/genética , China , DNA Bacteriano/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Ácidos Graxos/análise , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Folhas de Planta/microbiologia , Endófitos/genética , Endófitos/classificação , Endófitos/isolamento & purificaçãoRESUMO
The high diversity and global distribution of heterotrophic bacterial diazotrophs (HBDs) in the ocean has recently become apparent. However, understanding the role these largely uncultured microorganisms play in marine N2 fixation poses a challenge due to their undefined growth requirements and the complex regulation of the nitrogenase enzyme. We isolated and characterized Candidatus Thalassolituus haligoni, a member of a widely distributed clade of HBD belonging to the Oceanospirillales. Analysis of its nifH gene via amplicon sequencing revealed the extensive distribution of Cand. T. haligoni across the Pacific, Atlantic, and Arctic Oceans. Pangenome analysis indicates that the isolate shares >99% identity with an uncultured metagenome-assembled genome called Arc-Gamma-03, recently recovered from the Arctic Ocean. Through combined genomic, proteomic, and physiological approaches, we confirmed that the isolate fixes N2 gas. However, the mechanisms governing nitrogenase regulation in Cand. T. haligoni remain unclear. We propose Cand. T. haligoni as a globally distributed, cultured HBD model species within this understudied clade of Oceanospirillales.
Assuntos
Gammaproteobacteria , Fixação de Nitrogênio , Filogenia , Gammaproteobacteria/genética , Gammaproteobacteria/metabolismo , Gammaproteobacteria/isolamento & purificação , Gammaproteobacteria/enzimologia , Gammaproteobacteria/classificação , Nitrogenase/metabolismo , Nitrogenase/genética , Água do Mar/microbiologia , Metagenoma , OxirredutasesRESUMO
BACKGROUND: Phytobacter diazotrophicus (P. diazotrophicus) is an opportunistic pathogen that causes nosocomial outbreaks and sepsis. However, there are no reports of P. diazotrophicus isolated from human blood in China. CASE PRESENTATION: A 27-day-old female infant was admitted to our hospital with fever and high bilirubin levels. The clinical features included jaundice, abnormal coagulation, cholestasis, fever, convulsions, weak muscle tension, sucking weakness, ascites, abnormal tyrosine metabolism, cerebral oedema, abnormal liver function, clavicle fracture, and haemolytic anaemia. The strain isolated from the patient's blood was identified as P. diazotrophicus by whole-genome sequencing (WGS). Galactosemia type 1 (GALAC1) was diagnosed using whole-exome sequencing (WES). Based on drug sensitivity results, 10 days of anti-infective treatment with meropenem combined with lactose-free milk powder improved symptoms. CONCLUSION: P. diazotrophicus was successfully identified in a patient with neonatal sepsis combined with galactosemia. Galactosemia may be an important factor in neonatal sepsis. This case further expands our understanding of the clinical characteristics of GALAC1.
Assuntos
Galactosemias , Sepse , Humanos , Feminino , China , Galactosemias/complicações , Galactosemias/microbiologia , Sepse/microbiologia , Sepse/tratamento farmacológico , Sepse/complicações , Recém-Nascido , Antibacterianos/uso terapêutico , Meropeném/uso terapêutico , Sequenciamento Completo do Genoma , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificaçãoRESUMO
Antarctica, one of the most extreme environments on Earth, hosts diverse microbial communities. These microbes have evolved and adapted to survive in these hostile conditions, but knowledge on the molecular mechanisms underlying this process remains limited. The Italian Collection of Antarctic Bacteria (Collezione Italiana Batteri Antartici (CIBAN)), managed by the University of Messina, represents a valuable repository of cold-adapted bacterial strains isolated from various Antarctic environments. In this study, we sequenced and analyzed the genomes of 58 marine Gammaproteobacteria strains from the CIBAN collection, which were isolated during Italian expeditions from 1990 to 2005. By employing genome-scale metrics, we taxonomically characterized these strains and assigned them to four distinct genera: Pseudomonas, Pseudoalteromonas, Shewanella, and Psychrobacter. Genome annotation revealed a previously untapped functional potential, including secondary metabolite biosynthetic gene clusters and antibiotic resistance genes. Phylogenomic analyses provided evolutionary insights, while assessment of cold-shock protein presence shed light on adaptation mechanisms. Our study emphasizes the significance of CIBAN as a resource for understanding Antarctic microbial life and its biotechnological potential. The genomic data unveil new horizons for insight into bacterial existence in Antarctica.
Assuntos
Gammaproteobacteria , Genoma Bacteriano , Genômica , Filogenia , Regiões Antárticas , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Genômica/métodos , Psychrobacter/genética , Psychrobacter/isolamento & purificação , Pseudoalteromonas/genética , Família MultigênicaRESUMO
The genus Natronospira is represented by a single species of extremely salt-tolerant aerobic alkaliphilic proteolytic bacterium, isolated from hypersaline soda lakes. When cells of Gram-positive cocci were used as a substrate instead of proteins at extremely haloalkaline conditions, two new members of this genus were enriched and isolated in pure culture from the same sites. Strains AB-CW1 and AB-CW4 are obligate aerobic heterotrophic proteolytic bacteria able to feed on both live and dead cells of staphylococci and a range of proteins and peptides. Similar to the type species, N. proteinivora, the isolates are extremely salt-tolerant obligate alkaliphiles. However, N. proteinivora was unable to use bacterial cells as a substrate. Electron microscopy showed direct contact between the prey and predator cells. Functional analysis of the AB-CW1 and AB-CW4 genomes identified two sets of genes coding for extracellular enzymes potentially involved in the predation and proteolysis, respectively. The first set includes several copies of lysozyme-like GH23 peptidoglycan-lyase and murein-specific M23 [Zn]-di-peptidase enabling the cell wall degradation. The second set features multiple copies of secreted serine and metallopeptidases apparently allowing for the strong proteolytic phenotype. Phylogenomic analysis placed the isolates into the genus Natronospira as two novel species members, and furthermore indicated that this genus forms a deep-branching lineage of a new family (Natronospiraceae) and order (Natronospirales) within the class Gammaproteobacteria. On the basis of distinct phenotypic and genomic properties, strain AB-CW1T (JCM 335396 = UQM 41579) is proposed to be classified as Natronospira elongata sp. nov., and AB-CW4T (JCM 335397 = UQM 41580) as Natronospira bacteriovora sp. nov.
Assuntos
DNA Bacteriano , Gammaproteobacteria , Lagos , Filogenia , RNA Ribossômico 16S , Lagos/microbiologia , RNA Ribossômico 16S/genética , Gammaproteobacteria/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Gammaproteobacteria/fisiologia , DNA Bacteriano/genética , Análise de Sequência de DNA , Tolerância ao Sal , Técnicas de Tipagem Bacteriana , Composição de Bases , Genoma Bacteriano/genética , Ácidos Graxos/análiseRESUMO
In coastal marine ecosystems, kelp forests serve as a vital habitat for numerous species and significantly influence local nutrient cycles. Bull kelp, or Nereocystis luetkeana, is a foundational species in the iconic kelp forests of the northeast Pacific Ocean and harbours a complex microbial community with potential implications for kelp health. Here, we report the isolation and functional characterisation of 16 Nereocystis-associated bacterial species, comprising 13 Gammaproteobacteria, 2 Flavobacteriia and 1 Actinomycetia. Genome analyses of these isolates highlight metabolisms potentially beneficial to the host, such as B vitamin synthesis and nitrogen retention. Assays revealed that kelp-associated bacteria thrive on amino acids found in high concentrations in the ocean and in the kelp (glutamine and asparagine), generating ammonium that may facilitate host nitrogen acquisition. Multiple isolates have genes indicative of interactions with key elemental cycles in the ocean, including carbon, nitrogen and sulphur. We thus report a collection of kelp-associated microbial isolates that provide functional insight for the future study of kelp-microbe interactions.
Assuntos
Ecossistema , Kelp , Sequenciamento Completo do Genoma , Kelp/microbiologia , Kelp/metabolismo , Kelp/genética , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Nitrogênio/metabolismo , Genoma Bacteriano , Oceano Pacífico , Filogenia , Gammaproteobacteria/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/metabolismo , Gammaproteobacteria/isolamento & purificação , Água do Mar/microbiologia , Carbono/metabolismoRESUMO
The microbiome represents a complex network among the various members of the community of microorganisms that are associated with a host. The composition of the bacterial community is essential to supplement multiple metabolic pathways that the host lacks, particularly in organisms with blood-sucking habits such as ticks. On the other hand, some endosymbionts showed some competence with potentially pathogenic microorganisms. Francisella-like endosymbionts (FLEs) encompass a group of gamma-proteobacterias that are closely related to Francisella tularensis, but are usually apathogenic, which brings nutrients like vitamin B and other cofactors to the tick. It has been postulated that the main route of transmission of FLE is vertical; however, evidence has accumulated regarding the possible mechanism of horizontal transmission. Despite growing interest in knowledge of endosymbionts in the Neotropical region, the efforts related to the establishment of their inventory for tick communities are concentrated in South and Central America, with an important gap in knowledge in Mesoamerican countries such as Mexico. For this reason, the aim of this work was to evaluate the presence and diversity of endosymbionts in the highly host-specialized tick Amblyomma nodosum collected from the anteater Tamandua mexicana in Mexico. We analysed 36 A. nodosum for the presence of DNA of endosymbiont (Coxiella and Francisella) and pathogenic (Anaplasma, Borrelia, Ehrlichia and Rickettsia) bacteria. The presence of a member of the genus Francisella and Candidatus Anaplasma brasiliensis was demonstrated. Our findings provide information on the composition of A. nodosum's microbiome, increasing the inventory of bacterial species associated with this hard tick on the American continent.
Assuntos
Amblyomma , Gammaproteobacteria , Amblyomma/microbiologia , Animais , Vermilingua/parasitologia , México , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Masculino , Feminino , FilogeniaRESUMO
Wildlife play a role in the acquisition, maintenance, and dissemination of antimicrobial resistance (AMR). This is especially true at the human-domestic animal-wildlife interface, like urbanized areas, where interactions occur that can promote the cross-over of AMR bacteria and genes. We conducted a 2-year fecal surveillance (n = 783) of a white-tailed deer (WTD) herd from an urban park system in Ohio to identify and characterize cephalosporin-resistant and carbapenemase-producing bacteria using selective enrichment. Using generalized linear mixed models we found that older (OR = 2.3, P < 0.001), male (OR = 1.8, P = 0.001) deer from urbanized habitats (OR = 1.4, P = 0.001) were more likely to harbor extended-spectrum cephalosporin-resistant Enterobacterales. In addition, we isolated two carbapenemase-producing Enterobacterales (CPE), a Klebsiella quasipneumoniae harboring blaKPC-2 and an Escherichia coli harboring blaNDM-5, from two deer from urban habitats. The genetic landscape of the plasmid carrying blaKPC-2 was unique, not clustering with other reported plasmids encoding KPC-2, and only sharing 78% of its sequence with its nearest match. While the plasmid carrying blaNDM-5 shared sequence similarity with other reported plasmids encoding NDM-5, the intact IS26 mobile genetic elements surrounding multiple drug resistant regions, including the blaNDM-5, has been reported infrequently. Both carbapenemase genes were successfully conjugated to a J53 recipient conferring a carbapenem-resistant phenotype. Our findings highlight that urban environments play a significant role on the transmission of AMR bacteria and genes to wildlife and suggest WTD may play a role in the dissemination of clinically and epidemiologically relevant antimicrobial resistant bacteria. IMPORTANCE The role of wildlife in the spread of antimicrobial resistance is not fully characterized. Some wildlife, including white-tailed deer (WTD), can thrive in suburban and urban environments. This may result in the exchange of antimicrobial resistant bacteria and resistance genes between humans and wildlife, and lead to their spread in the environment. We found that WTD living in an urban park system carried antimicrobial resistant bacteria that were important to human health and resistant to antibiotics used to treat serious bacterial infections. This included two deer that carried bacteria resistant to carbapenem antibiotics which are critically important for treatment of life-threatening infections. These two bacteria had the ability to transfer their AMR resistance genes to other bacteria, making them a threat to public health. Our results suggest that WTD may contribute to the spread of antimicrobial resistant bacteria in the environment.
Assuntos
Cefalosporinase , Cervos , Farmacorresistência Bacteriana , Gammaproteobacteria/isolamento & purificação , Animais , Animais Selvagens/microbiologia , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Cefalosporinase/genética , Cefalosporinas/farmacologia , Cervos/microbiologia , Gammaproteobacteria/efeitos dos fármacos , Humanos , Masculino , Testes de Sensibilidade Microbiana , PlasmídeosRESUMO
Characterization of the microbial community is essential for understanding the symbiotic relationships between microbes and host insects. Chrysomya megacephala is a vital resource, a forensic insect, a pollinator, and a vector for enteric bacteria, protozoa, helminths, and viruses. However, research on its microbial community is incomprehensive, particularly at the pupal stage, which comprises approximately half of the entire larval development stage and is important entomological evidence in forensic medicine. For the first time, this study investigated the bacterial communities of C. megacephala pupae at different ages using third-generation sequencing technology. The results showed that C. megacephala has a diverse and dynamic bacterial community. Cluster analysis at ≥ 97% similarity produced 154 operational taxonomic units (OTUs) that belonged to 10 different phyla and were distributed into 15 classes, 28 orders, 50 families, 88 genera, and 130 species. Overall, the number of bacterial OTUs increased with the development of pupae, and the relative abundance of Wolbachia in the Day5 group was significantly lower than that in the other groups. Within the pupal stage, Proteobacteria, Firmicutes, and Bacteroidetes were the dominant phyla of bacteria. At the genus level, Wolbachia and Ignatzschineria coexisted, a rarely known feature. In addition, we found Erysipelothrix rhusiopathiae, the etiological agent of swine erysipelas, which is rarely identified in insects. This study enriches the understanding of the microbial community of C. megacephala and provides a reference for better utilization and control of C. megacephala.
Assuntos
Calliphoridae/microbiologia , Microbiota , Pupa/microbiologia , Análise de Sequência de RNA/métodos , Animais , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Bacteroidetes/fisiologia , Erysipelothrix/genética , Erysipelothrix/isolamento & purificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Firmicutes/fisiologia , Entomologia Forense , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Gammaproteobacteria/fisiologia , Microbiota/genética , Microbiota/fisiologia , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Proteobactérias/fisiologia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Simbiose , Wolbachia/genética , Wolbachia/isolamento & purificação , Wolbachia/fisiologiaRESUMO
Rhodanobacter species dominate in the Oak Ridge Reservation (ORR) subsurface environments contaminated with acids, nitrate, metal radionuclides, and other heavy metals. To uncover the genomic features underlying adaptations to these mixed-waste environments and to guide genetic tool development, we sequenced the whole genomes of eight Rhodanobacter strains isolated from the ORR site. The genome sizes ranged from 3.9 to 4.2 Mb harboring 3,695 to 4,035 protein-coding genes and GC contents approximately 67%. Seven strains were classified as R. denitrificans and one strain, FW510-R12, as R. thiooxydans based on full length 16S rRNA sequences. According to gene annotation, the top two Cluster of Orthologous Groups (COGs) with high pan-genome expansion rates (Pan/Core gene ratio) were "replication, recombination and repair" and "defense mechanisms." The denitrifying genes had high DNA homologies except the predicted protein structure variances in NosZ. In contrast, heavy metal resistance genes were diverse with between 7 to 34% of them were located in genomic islands, and these results suggested origins from horizontal gene transfer. Analysis of the methylation patterns in four strains revealed the unique 5mC methylation motifs. Most orthologs (78%) had ratios of nonsynonymous to synonymous substitutions (dN/dS) less than one when compared to the type strain 2APBS1, suggesting the prevalence of negative selection. Overall, the results provide evidence for the important roles of horizontal gene transfer and negative selection in genomic adaptation at the contaminated field site. The complex restriction-modification system genes and the unique methylation motifs in Rhodanobacter strains suggest the potential recalcitrance to genetic manipulation. IMPORTANCE Despite the dominance of Rhodanobacter species in the subsurface of the contaminated Oak Ridge Reservation (ORR) site, very little is known about the mechanisms underlying their adaptions to the various stressors present at ORR. Recently, multiple Rhodanobacter strains have been isolated from the ORR groundwater samples from several wells with varying geochemical properties. Using Illumina, PacBio, and Oxford Nanopore sequencing platforms, we obtained the whole genome sequences of eight Rhodanobacter strains. Comparison of the whole genomes demonstrated the genetic diversity, and analysis of the long nanopore reads revealed the heterogeneity of methylation patterns in strains isolated from the same well. Although all strains contained a complete set of denitrifying genes, the predicted tertiary structures of NosZ differed. The sequence comparison results demonstrate the important roles of horizontal gene transfer and negative selection in adaptation. In addition, these strains may be recalcitrant to genetic manipulation due to the complex restriction-modification systems and methylations.
Assuntos
Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Nitratos/análise , Poluentes Químicos da Água/análise , Composição de Bases , Gammaproteobacteria/classificação , Gammaproteobacteria/metabolismo , Transferência Genética Horizontal , Tamanho do Genoma , Genoma Bacteriano , Ilhas Genômicas , Genômica , Água Subterrânea/microbiologia , Metais Pesados/análise , Metais Pesados/metabolismo , Nitratos/metabolismo , Filogenia , Poluentes Químicos da Água/metabolismoRESUMO
Decreased susceptibility to carbapenems in Enterobacterales is an emerging concern. Conventional methods with short turnaround times are crucial for therapeutic decisions and infection control. In the current study, we used the Xpert CARBA-R (Cepheid, Sunnyvale, CA, USA) and the NG-Test CARBA 5 (NG Biotech, Guipry, France) assays for carbapenemase detection in 214 carbapenem-resistant Enterobacterales (CRE) blood isolates. We used the modified carbapenem inactivation method, conventional PCR, and sequencing to determine the production of five common carbapenemase families and their subtypes. We performed wzc-genotyping for all CR-Klebsiella pneumoniae (CRKP) and multilocus sequence typing for all carbapenemase-producing CRE isolates to reveal their genetic relatedness. The results showed a sensitivity of 99.8% and a specificity of 100% by the Xpert assay, and a sensitivity of 100% and a specificity of 99% by the NG-Test in detecting carbapenemases of 84 CRKP isolates with only one (VIM-1+IMP-8) failure in both tests. For CR-Escherichia coli, four carbapenemase-producing isolates were detected accurately for their subtypes. The two major clones of carbapenemase-producing CRKP isolates in Taiwan were ST11-K47 producing KPC-2 (n = 47) and ST11-K64 producing OXA-48-like (n = 9). Our results support the use of either test in routine laboratories for the rapid detection of common carbapenemases. Caution should be taken using the Xpert assay in areas with a high prevalence of CRE carrying blaIMP-8. IMPORTANCE Carbapenemase-producing Enterobacterales (CPE) are emerging worldwide, causing nosocomial outbreaks and even community-acquired infections since their appearance 2 decades ago. Our previous national surveillance of CPE isolates in Taiwan identified five carbapenemase families (KPC, OXA, NDM, VIM, and IMP) with the KPC-2 and OXA-48-like types predominant. Timely detection and classification of carbapenemases in CPE may be a useful test to guide optimal therapy and infection control. Genetic detection methods using the Xpert CARBA-R assay and the immunochromatographic assay using the NG-Test CARBA 5 have been validated with the advantage of short turnaround time. Our study demonstrated that the NG and Xpert assays are convenient methods to accurately identify carbapenemases in carbapenem-resistant Klebsiella pneumoniae and carbapenem-resistant Escherichia coli blood isolates. Detecting IMP variants remains challenging, and the results of Xpert CARBA-R assay should be carefully interpreted.
Assuntos
Carbapenêmicos/farmacologia , Infecções por Enterobacteriaceae/diagnóstico , Gammaproteobacteria/efeitos dos fármacos , Gammaproteobacteria/isolamento & purificação , Imunoensaio/métodos , Sepse/diagnóstico , Proteínas de Bactérias , Carbapenêmicos/uso terapêutico , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Sepse/tratamento farmacológico , Sepse/microbiologia , beta-LactamasesRESUMO
BACKGROUND: Psyllids (Hemiptera: Psylloidea) comprise a group of plant sap-sucking insects that includes important agricultural pests. They have close associations not only with plant pathogens, but also with various microbes, including obligate mutualists and facultative symbionts. Recent studies are revealing that interactions among such bacterial populations are important for psyllid biology and host plant pathology. In the present study, to obtain further insight into the ecological and evolutionary behaviors of bacteria in Psylloidea, we analyzed the microbiomes of 12 psyllid species belonging to the family Psyllidae (11 from Psyllinae and one from Macrocorsinae), using high-throughput amplicon sequencing of the 16S rRNA gene. RESULTS: The analysis showed that all 12 psyllids have the primary symbiont, Candidatus Carsonella ruddii (Gammaproteobacteria: Oceanospirillales), and at least one secondary symbiont. The majority of the secondary symbionts were gammaproteobacteria, especially those of the family Enterobacteriaceae (order: Enterobacteriales). Among them, symbionts belonging to "endosymbionts3", which is a genus-level monophyletic group assigned by the SILVA rRNA database, were the most prevalent and were found in 9 of 11 Psyllinae species. Ca. Fukatsuia symbiotica and Serratia symbiotica, which were recognized only as secondary symbionts of aphids, were also identified. In addition to other Enterobacteriaceae bacteria, including Arsenophonus, Sodalis, and "endosymbionts2", which is another genus-level clade, Pseudomonas (Pseudomonadales: Pseudomonadaceae) and Diplorickettsia (Diplorickettsiales: Diplorickettsiaceae) were identified. Regarding Alphaproteobacteria, the potential plant pathogen Ca. Liberibacter europaeus (Rhizobiales: Rhizobiaceae) was detected for the first time in Anomoneura mori (Psyllinae), a mulberry pest. Wolbachia (Rickettsiales: Anaplasmataceae) and Rickettsia (Rickettsiales: Rickettsiaceae), plausible host reproduction manipulators that are potential tools to control pest insects, were also detected. CONCLUSIONS: The present study identified various bacterial symbionts including previously unexpected lineages in psyllids, suggesting considerable interspecific transfer of arthropod symbionts. The findings provide deeper insights into the evolution of interactions among insects, bacteria, and plants, which may be exploited to facilitate the control of pest psyllids in the future.
Assuntos
Gammaproteobacteria/isolamento & purificação , Hemípteros/microbiologia , Microbiota , Animais , Afídeos/microbiologia , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Hemípteros/classificação , Liberibacter/classificação , Liberibacter/genética , Liberibacter/isolamento & purificação , Filogenia , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Rickettsia/classificação , Rickettsia/genética , Rickettsia/isolamento & purificação , Serratia/classificação , Serratia/genética , Serratia/isolamento & purificação , Simbiose , Wolbachia/classificação , Wolbachia/genética , Wolbachia/isolamento & purificaçãoRESUMO
A Gram-stain-negative, rod-shaped bacterial strain, designated SW123T, was isolated from a deep-sea water sample collected from the Indian Ocean. Strain SW123T was strictly aerobic, catalase- and oxidase-positive. The predominant cellular fatty acids were iso-C15 : 0, iso-C17 : 0 and summed feature 9 (comprising C16 : 0-methyl or iso-C17 : 1 ω9c). Ubiquinone-8 was the sole respiratory quinone. The major polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The genomic DNA G+C content was 49.4 mol%. 16S rRNA gene sequence analysis showed that strain SW123T was closely related to Aliidiomarina shirensis AIST (96.7 % sequence similarity), Aliidiomarina iranensis GBPy7T (96.3%), Aliidiomarina haloalkalitolerans AK5T (96.0%) and Aliidiomarina celeris F3105T (95.9%). Phylogenetic trees based on 16S rRNA gene sequences showed that strain SW123T represented a novel member of the genus Aliidiomarina, forming a distinct cluster with A. celeris F3105T. On the basis of phylogenetic inference and phenotypic characteristics, we propose that strain SW123T represents a novel species of the genus Aliidiomarina, with the name Aliidiomarina indica sp. nov. The type strain is SW123T (=CGMCC1.16169T=KCTC 82234T).
Assuntos
Gammaproteobacteria/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Gammaproteobacteria/isolamento & purificação , Oceano Índico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
A Gram-stain-negative, aerobic, rod-shaped and non-motile novel bacterial strain, designated MAH-13T, was isolated from a soil sample. The colonies were observed to be yellow-coloured, smooth, spherical and 1.8-3.0 mm in diameter when grown on nutrient agar medium for 2 days. Strain MAH-13T was found to be able to grow at 20-40 °C, at pH 5.0-10.0 and with 0-1.0% NaCl (w/v). Cell growth occurred on tryptone soya agar, Luria-Bertani agar, nutrient agar and Reasoner's 2A agar. The strain was found to be positive for both oxidase and catalase tests. The strain was positive for hydrolysis of casein, starch, DNA and l-tyrosine. According to 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Frateuria and to be closely related to Frateuria terrea DSM 26515T (98.2% similarity), Dyella thiooxydans ATSB10T (98.2â%), Frateuria defendens HyOGT (97.9â%), Rhodanobacter glycinis MO64T (97.8â%) and Frateuria aurantia DSM 6220T (97.8â%). The novel strain MAH-13T has a draft genome size of 3â682â848 bp (40 contigs), annotated with 3172 protein-coding genes, 49 tRNA genes and three rRNA genes. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain MAH-13T and five closely related type strains were in the range of 73.7-85.5 % and 20.7-30.1%, respectively. The genomic DNA G+C content was determined to be 68.0 mol%. The predominant isoprenoid quinone was ubiquinone 8. The major fatty acids were identified as iso-C15:0, iso-C16:0 and summed feature 9 (iso-C17â:â1 ω9c and/or C16:0 10-methyl). On the basis of dDDH and ANI values, genotypic analysis, and chemotaxonomic and physiological data, strain MAH-13T represents a novel species within the genus Frateuria, for which the name Frateuria flava sp. nov. is proposed, with MAH-13T (=KACC 19743T=CGMCC 1.13655T) as the type strain.
Assuntos
Gammaproteobacteria/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Gammaproteobacteria/isolamento & purificação , Hibridização de Ácido Nucleico , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/químicaRESUMO
Whitefly, Bemisia tabaci (Gennadius) is an important pest of cotton causing direct damage as sap feeder and vector of Cotton leaf curl virus (CLCuV). Previous few studies suggest that female whiteflies are more efficient vector of begomovirusthan males, however the sex-biased transmission efficiency is still not clearly understood. Present studies with B. tabaci AsiaII-1 haplotype showed higher virus transmission efficiency of females compared to males. This variable begomovirus transmission efficiency has been related to previously identifiedkey factors associated with B. tabaci. The higher density of endosymbiont Arsenophonus and variable expression of some midgut proteins genes i.e. Cyclophilin, Knottin, Hsp40, Hsp70 may be possibly imparting higher vector competency to the females compared to males. The present studies suggest low abundance of Arsenophonus spp. as well as lower expressionof Cyclophilin genein males as compared to females. This is further supplemented by overexpression of Knottin, Hsp40, and Hsp70 genes in males compared to females and thus collectively all these factors might be playing a key role in low virus transmission efficiency of males. The relative density of Arsenophonus spp. and expression of midgut proteins genes in male and female whitefly first time enriches our understanding about sex-biased transmission efficiency of begomovirus.
Assuntos
Begomovirus/fisiologia , Sistema Digestório/metabolismo , Gammaproteobacteria/crescimento & desenvolvimento , Hemípteros/virologia , Proteínas de Insetos/metabolismo , Animais , Begomovirus/crescimento & desenvolvimento , Ciclofilinas/antagonistas & inibidores , Ciclofilinas/genética , Ciclofilinas/metabolismo , Feminino , Gammaproteobacteria/isolamento & purificação , Gammaproteobacteria/fisiologia , Regulação da Expressão Gênica , Inativação Gênica , Proteínas de Choque Térmico HSP40/antagonistas & inibidores , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Haplótipos , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/genética , Insetos Vetores/virologia , Masculino , Doenças das Plantas/virologia , RNA de Cadeia Dupla/metabolismo , Fatores Sexuais , Simbiose , Carga ViralRESUMO
A novel bacterial strain, designated IPMB12T, isolated from the gut of the superworm Zophobas morio in Taiwan, was characterized using a polyphasic taxonomic approach. Cells were Gram-stain-negative, facultatively anaerobic, non-motile, coccoid or rod-shaped and formed translucent colonies. Optimal growth occurred at 25-37 °C, pH 9-10, and with 0-2â% NaCl. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain IPMB12T is affiliated with genus in the the family Orbaceae in the class Gammaproteobacteria. Strain IPMB12T was most closely related to Gilliamella mensalis LMG 29880T with a 94.6â% 16S rRNA gene sequence similarity. Strain IPMB12T showed less than 71.6â% average nucleotide identity, less than 71.5â% average amino acid identity and less than 21.2â% digital DNA-DNA hybridization identity compared to the strains of related genera within the family Orbaceae. The major fatty acids of strain IPMB12T were summed feature 8 (C18â:â1 ω7c and/or C18â:â1 ω6c), C16â:â0 and C14â:â0. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one uncharacterized phosphoaminoglycolipid and one uncharacterized aminophospholipid. The major isoprenoid quinone was Q-8. Genomic DNA G+C content of strain IPMB12T was 39.3 mol%. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain IPMB12T represents a novel species of a new genus in the family Orbaceae, for which the name Zophobihabitans entericus gen. nov., sp. nov. is proposed. The type strain is IPMB12T (=BCRC 80908T =LMG 32079T=KCTC 82347T=KACC 22323T).
Assuntos
Ácidos Graxos , Gammaproteobacteria , Invertebrados/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Taiwan , Ubiquinona/químicaRESUMO
A Gram-stain-negative, aerobic, rod-shaped strain (R2A-3T) was isolated from the toxin-producing dinoflagellate Centrodinium punctatum and identified as a novel genus and new species based on a polyphasic taxonomic approach. The optimum conditions for growth of the strain were at 25 °C, pH 8.0 and in the presence of 3â% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA genes and 92 core genes sets revealed that strain R2A-3T belongs to the family Nevskiaceae in the class Gammaproteobacteria and represented an independent taxon separated from other genera. The 16S rRNA gene of strain R2A-3T showed the highest sequence similarity to Polycyclovorans algicola TG408T (95.2%), Fontimonas thermophila HA-01T (94.1%) and Sinimarinibacterium flocculans NH6-24T (93.2%), and less than 92.8â% similarity to other genera in the family Nevskiaceae. The genome length of strain R2A-3T was 3608892 bp with 65.2âmol% G+C content. Summed feature 8 (comprising C18â:â1 ω7c and/or C18â:â1 ω6c) was the major fatty acid (>10â%). Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were detected as the major polar lipids. The major respiratory quinone was ubiquinone-8. According to its phylogenetic, phenotypic, chemotaxonomic and genomic features, strain R2A-3T represents a new species in the new genus of the family Nevskiaceae. It is recommended to name it Flagellatimonas centrodinii gen. nov., sp. nov. The type strain is R2A-3T (=KCTC 82469T=GDMCC 1.2523T).
Assuntos
Dinoflagellida , Gammaproteobacteria/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Dinoflagellida/microbiologia , Ácidos Graxos/química , Gammaproteobacteria/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/químicaRESUMO
The rapid detection of extended-spectrum ß-lactamase Enterobacterales (ESBL-E) in a positive blood culture is important in order to initiate an appropriate antibiotic therapy and thus decrease mortality. We evaluated the new BL-RED (ß-Lactamase Rapid Electrochemical Detection) test in 100 positive blood culture broths to detect (in ten minutes) the presence or absence of ESBL-E. The BL-RED test appears to be an easy, rapid and reliable test to detect the presence of ESBL directly in Gram negative bacilli-positive blood culture broths, with good performances (sensibility =97.3%, specificity =90.5%, predictive positive value =85.7% and predictive negative value =98.3%). This test could be useful for therapeutic decisions and adjustments of sepsis empirical antibiotic therapy, particularly in wards where the ecology is unfavorable, such as in intensive care units.
Assuntos
Hemocultura/métodos , Gammaproteobacteria/enzimologia , Gammaproteobacteria/isolamento & purificação , beta-Lactamases/análise , Antibacterianos/farmacologia , Gammaproteobacteria/efeitos dos fármacos , HumanosRESUMO
The genus Spartinivicinus, affiliated to the class Gammaproteobacteria, is an important marine member that produces prodiginines. Currently, its taxonomic assignment to family level is not well presented. Phylogeny of 16S rRNA gene sequences indicated that Spartinivicinus forms a monophyletic clade with Zooshikella, which is neighboured by Aestuariirhabdus of the family Aestuariirhabdaceae and another monophyletic clade of the family Endozoicomonadaceae. The 16S rRNA gene of Spartinivicinus ruber S2-4-1HT had sequence similarities to those of Aestuariirhabdus litorea GTF13T, Zooshikella members and Endozoicomonas members of 93.4%, 93.2-93.4â and <92.5â%, respectively. Phylogenomic analysis based on 120 bacterial conserved single-copy genes highly supported placing Spartinivicinus as a sister member of Zooshikella, neighboured by Aestuariirhabdaceae and Endozoicomonadaceae members, indicating that Spartinivicinus and Zooshikella could be considered to belong to the same family. Thus, Zooshikellaceae fam. nov. is proposed to accommodate the two genera. Colonies of Spartinivicinus and Zooshikella are red-pigmented, which is different from Aestuariirhabdus (pale-yellow pigmented). The major respiratory quinone of S. ruber was ubiquinone (Q-9), similar to Zooshikella, but distinct from Aestuariirhabdus (Q-9 and Q-8). The predominant fatty acids and polar lipids of Spartinivicinus also showed a similar patterns to Zooshikella, but they were different from Aestuariirhabdus. Lastly, Spartinivicinus possessed a genome size of 6.68 Mbp and DNA G+C content of 40.1mol%, similar to Zooshikella, but much larger than Aestuariirhabdus. In addition, the 16S rRNA genes of Z. ganghwensis JC2044T and Z. marina JC333T possess sequence similarity of 99.79â%. Whole genome comparisons indicated that they shared 79.8â% digital DNA-DNA hybridization, 97.78â% average nucleotide identity and 97.31â% average amino acid identity values. Activities of catalase and oxidase for the two strains were positive. Hydrolysis of skimmed milk and Tweens (40, 60 and 80) was positive. Interestingly, the two strains produced different kinds of prodiginines. We propose that Z. marina is a later heterotypic synonym of Zooshikella ganghwensis.
Assuntos
Gammaproteobacteria , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Hibridização de Ácido Nucleico , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/químicaRESUMO
Cells of bacterial strains G9T and 7MK23T, isolated from forest soil samples collected from the Dinghushan Biosphere Reserve, Guangdong Province, PR China, were Gram-stain-negative, aerobic and rod-shaped. Strain G9T was motile with single polar flagellum and grew at 12-37 °C (optimum, 28 °C), pH 4.5-8.0 (optimum, pH 6.0-7.5) and in the presence of 0-3.5â% NaCl (optimum, 1.5%, w/v); while strain 7MK23T was non-motile and grew at 12-42 °C (optimum, 28-33 °C), pH 2.5-8.5 (optimum, pH 4.5-6.5) and NaCl levels of 0-1.0â% (optimum, 0-0.5â%, w/v). Phylogenetic analysis based on 16S rRNA gene sequences revealed that both isolates fell within the cluster of the genus Dyella. The closely related species (with a 16S rRNA gene sequence similarity >98.65%) of strain G9T were Dyella terrae JS14-6T (99.0â%), D. kyungheensis THG-B117T (98.8â%) and D. amyloliquefaciens DHC06T (98.7â%) while that of strain 7MK23T were D. mobilis DHON07T (99.2â%) and D. flava DHOC52T (99.1â%), but the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strains G9T, 7MK23T and the closely related Dyella species listed above were in the ranges of 77.5-83.8â% and 22.0-27.0â%, much lower than the species demarcation lines of 95.5 and 70â%, respectively. Phylogenomic analyses using UBCG and Phylophlan also supported that these two strains represent two novel species of Dyella. The major fatty acids of strain G9T were iso-C15â:â0, iso-C17â:â1 ω9c and iso-C17â:â0 while that of strain 7MK23T were iso-C15â:â0 and anteiso-C15â:â0. Ubiquinone-8 was the only respiratory quinone detected in both strains. The polar lipids of strain G9T consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, and several unknown phospholipids, aminophospholipids, aminolipids and lipid while strain 7MK23T contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine and several unknown phospholipids and aminophospholipids. The DNA G+C contents of strains G9T and 7MK23T were 64.7 and 63.4 mol%, respectively. On the basis of 16S rRNA gene sequence phylogenetic and phylogenomic analyses as well as phenotypic data obtained, we propose that strains G9T and 7MK23T represent two novel species of the genus Dyella, for which the names Dyella telluris sp. nov. (type strain G9T=KACC 21725T=GDMCC 1.2132T) and Dyella acidiphila sp. nov. (type strain 7MK23T=KCTC 62739T=GDMCC 1.1446T) are proposed.