RESUMO
A Gram-negative, strictly aerobic bacterial strain was isolated from asymptomatic leaf tissue of a wild yam plant. Optimal growth was observed at 28â°C and pH 7, and catalase and oxidase activities were detected. Polyphasic taxonomic and comparative genomics revealed that strain LMG 33091T represents a novel species of Pseudomonas. The nearest phylogenetic neighbours of strain LMG 33091T were Pseudomonas putida NBRC 14164T (with 99.79â% 16S rRNA sequence identity), Pseudomonas alkylphenolica KL28T (99.28â%) and Pseudomonas asplenii (99.07â%) ATCC 23835T. MALDI-TOF MS analysis yielded distinct profiles for strain LMG 33091T and the nearest phylogenetic neighbours. Average nucleotide identity analyses between the whole genome sequence of strain LMG 33091T and of the type strains of its nearest-neighbour taxa yielded values below the species delineation threshold and thus confirmed that the strain represented a novel Pseudomonas species, for which we propose the name Pseudomonas fortuita sp. nov., with strain LMG 33091T (=GMI12077T= CFBP 9143T) as the type strain.
Assuntos
Técnicas de Tipagem Bacteriana , DNA Bacteriano , Dioscorea , Filogenia , Folhas de Planta , Pseudomonas , RNA Ribossômico 16S , Análise de Sequência de DNA , Sequenciamento Completo do Genoma , Pseudomonas/isolamento & purificação , Pseudomonas/genética , Pseudomonas/classificação , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Folhas de Planta/microbiologia , Dioscorea/microbiologia , Composição de Bases , Ácidos Graxos/análise , Genoma BacterianoRESUMO
We have previously isolated a gram-negative microaerophilic strain, PAGU2000T from a patient presenting with a fever in Kumamoto Prefecture, Japan. The present study aimed to comprehensively analyze the taxonomy of the isolated strain using a polyphasic approach. The 16S rRNA gene sequence analysis indicated that the strain was a member of enterohepatic Helicobacter. The strain PAGU2000T shared a 97.5% 16S rRNA gene nucleotide identity with Helicobacter valdiviensis, and this taxonomic position was confirmed by phylogenetic analysis of the GyrA amino acid sequences. The proposed strain PAGU2000T has a 1.482 Mbp chromosome with a DNA G + C content of 31.3 mol% and encodes 1520 predicted coding sequences. The average nucleotide identity between the strain PAGU2000T and type strain of H. valdiviensis was 70.3%, which was lower than the recommended threshold of 95% for species delineation. The strain PAGU2000T was a motile, non-spore-forming, and spiral-shaped bacterium, exhibiting catalase and oxidase activities but not urease and nitrate reduction. This study demonstrates that the isolate represents a novel species within enterohepatic Helicobacter, for which the name Helicobacter higonensis is proposed (type strain: PAGU2000T = GTC 16811T = LMG 33095T). In this study, we describe the phenotypic and morphological features of this strain and propose an emended description of some biochemical traits of H. valdiviensis.
Assuntos
Composição de Bases , DNA Bacteriano , Infecções por Helicobacter , Helicobacter , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Helicobacter/genética , Helicobacter/classificação , Helicobacter/isolamento & purificação , RNA Ribossômico 16S/genética , Humanos , DNA Bacteriano/genética , Infecções por Helicobacter/microbiologia , Japão , Técnicas de Tipagem Bacteriana , DNA Girase/genéticaRESUMO
The production of gueuze beers through refermentation and maturation of blends of lambic beer in bottles is a way for lambic brewers to cope with the variability among different lambic beer batches. The resulting gueuze beers are more carbonated than lambic beers and are supposed to possess a unique flavor profile that varies over time. To map this refermentation and maturation process for gueuze production, a blend of lambic beers was made and bottled, whereby one of them was produced with the old wheat landrace Zeeuwse Witte. Through the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and high-throughput sequencing of bacterial and fungal amplicons, in combination with metabolite target analysis, new insights into gueuze production were obtained. During the initial stages of refermentation, the conditions in the bottles were similar to those encountered during the maturation phase of lambic beer productions in wooden barrels, which was also reflected microbiologically (presence of Brettanomyces species, Pediococcus damnosus, and Acetobacter lambici) and biochemically (ethanol, higher alcohols, lactic acid, acetic acid, volatile phenolic compounds, and ethyl esters). However, after a few weeks of maturation, a switch from a favorable environment to one with nutrient and dissolved oxygen depletion resulted in several changes. Concerning the microbiology, a sequential prevalence of three lactic acid bacterial species occurred, namely, P. damnosus, Lentilactobacillus buchneri, and Lactobacillus acetotolerans, while the diversity of the yeasts decreased. Concerning the metabolites produced, mainly those of the Brettanomyces yeasts determined the metabolic profiles encountered during later stages of the gueuze production.IMPORTANCEGueuze beers are the result of a refermentation and maturation process of a blend of lambic beers carried out in bottles. These gueuze beers are known to have a long shelf life, and their quality typically varies over time. However, knowledge about gueuze production in bottles is scarce. The present study provided more insights into the varying microbial and metabolite composition of gueuze beers during the first 2 years of this refermentation and maturation process. This will allow gueuze producers to gain more information about the influence of the refermentation and maturation time on their beers. These insights can also be used by gueuze producers to better inform their customers about the quality of young and old gueuze beers.
Assuntos
Cerveja , Brettanomyces , Cerveja/microbiologia , Fermentação , Etanol/análise , Ácido LácticoRESUMO
Type 3 sourdoughs, which are starter culture-initiated and subsequently backslopped, are less studied than other sourdough types. Yet, they can serve as a model to assess how competitive starter culture strains for sourdough production are and how the microbial composition of such sourdoughs may evolve over time. In the present study, Limosilactobacillus fermentum IMDO 130101 was used to produce Type 3 sourdoughs, prepared from wheat and wholemeal wheat flours. Therefore, an initial fermentation of the flour-water mixture was performed at 30 °C for 48 h. This was followed by cold storage-backslopping cycles, consisting of refreshments (50 %, v/v), fermentation steps of 16 h, and storage at 4 °C each week, every three weeks, and every six weeks. The microbial dynamics (culture-dependent and -independent approaches) and metabolite dynamics were measured. In all sourdoughs produced, starter culture strain monitoring, following an amplicon sequence variant approach, showed that Liml. fermentum IMDO 130101 prevailed during one month when the sourdoughs were refreshed each week, during 24 weeks when the sourdoughs were refreshed every three weeks, and during 12 weeks when the sourdoughs were refreshed every six weeks. This suggested the competitiveness and robustness of Liml. fermentum IMDO 130101 for a considerable duration but also showed that the strain is prone to microbial interference. For instance, Levilactobacillus brevis and Pediococcus spp. prevailed upon further cold storage and backslopping. Also, although no yeasts were inoculated into the flour-water mixtures, Kazachstania unispora, Torulaspora delbrueckii, and Wickerhamomyces anomalus were the main yeast species found. They appeared after several weeks of storage and backslopping, which however indicated the importance of an interplay between LAB and yeast species in sourdoughs. The main differences among the mature sourdoughs obtained could be explained by the different flours used, the refreshment conditions applied, and the sampling time (before and after backslopping). Finally, the metabolite quantifications revealed continued metabolite production during the cold storage periods, which may impact the sourdough properties and those of the breads made thereof.
Assuntos
Limosilactobacillus fermentum , Torulaspora , Pediococcus , Pão , Farinha , Fermentação , ÁguaRESUMO
We characterized the microbial communities of the crop, midgut, hindgut, and ovaries of the wild solitary bees Andrena vaga, Anthophora plumipes, Colletes cunicularius, and Osmia cornuta through 16S rRNA gene and ITS2 amplicon sequencing and a large-scale isolation campaign. The bacterial communities of these bees were dominated by endosymbionts of the genera Wolbachia and Spiroplasma. Bacterial and yeast genera representing the remaining predominant taxa were linked to an environmental origin. While only a single sampling site was examined for Andrena vaga, Anthophora plumipes, and Colletes cunicularius, and two sampling sites for Osmia cornuta, the microbiota appeared to be host specific: bacterial, but not fungal, communities generally differed between the analyzed bee species, gut compartments and ovaries. This may suggest a selective process determined by floral and host traits. Many of the gut symbionts identified in the present study are characterized by metabolic versatility. Whether they exert similar functionalities within the bee gut and thus functional redundancy remains to be elucidated.
Assuntos
Microbiota , Micobioma , Spiroplasma , Abelhas , Animais , RNA Ribossômico 16S/genética , BactériasRESUMO
The genus Periweissella was proposed as a novel genus in the Lactobacillaceae in 2022. However, the phylogenetic relationship between Periweissella and other heterofermentative lactobacilli, and the genetic and physiological properties of this genus remain unclear. This study aimed to determine the phylogenetic relationship between Periweissella and the two closest genera, Weissella and Furfurilactobacillus, by the phylogenetic analysis and calculation of (core gene) pairwise average amino acid identity. Targeted genomic analysis showed that fructose bisphosphate aldolase was only present in the genome of Pw. cryptocerci. Mannitol dehydrogenase was found in genomes of Pw. beninensis, Pw. fabaria, and Pw. fabalis. Untargeted genomic analysis identified the presence of flagellar genes in Periweissella but not in other closely related genera. Phenotypes related to carbohydrate fermentation and motility matched the genotypes. Motility genes were organized in a single operon and the proteins shared a high amino acid similarity in the genus Periweissella. The relatively low similarity of motility operons between Periweissella and other motile lactobacilli indicated the acquisition of motility by the ancestral species. Our findings facilitate the phylogenetic, genetic, and phenotypic understanding of the genus Periweissella.ImportanceThe genus Periweissella is a heterofermentative genus in the Lactobacillaceae which includes predominantly isolates from cocoa fermentations in tropical climates. Despite the relevance of the genus in food fermentations, genetic and physiological properties of the genus are poorly characterized and genome sequences became available only after 2020. This study characterized strains of the genus by functional genomic analysis, and by determination of metabolic and physiological traits. Phylogenetic analysis revealed that Periweissella is the evolutionary link between rod-shaped heterofermentative lactobacilli and the coccoid Leuconostoc clade with the genera Weissella and Furfurilactobacillus as closest relatives. Periweissella is the only heterofermentative genus in the Lactobacillaceae which comprises predominantly motile strains. The genomic, physiological, and metabolic characterization of Periweissella may facilitate the potential use of strains of the genus as starter culture in traditional or novel food fermentations.
Assuntos
Lactobacillaceae , Weissella , Filogenia , Lactobacillaceae/metabolismo , Lactobacillus/genética , Weissella/genética , Weissella/metabolismo , Genômica , Aminoácidos/metabolismo , Fermentação , RNA Ribossômico 16S/genéticaRESUMO
We provide a culturomics analysis of the cultivable bacterial communities of the crop, midgut and hindgut compartments, as well as the ovaries, of the invasive insect Vespa velutina, along with a cultivation-independent analysis of samples of the same nest through 16S rRNA amplicon sequencing. The Vespa velutina bacterial symbiont community was dominated by the genera Convivina, Fructobacillus, Lactiplantibacillus, Lactococcus, Sphingomonas and Spiroplasma. Lactococcus lactis and Lactiplantibacillus plantarum represented generalist core lactic acid bacteria (LAB) symbionts, while Convivina species and Fructobacillus fructosus represented highly specialised core LAB symbionts with strongly reduced genome sizes. Sphingomonas and Spiroplasma were the only non-LAB core symbionts but were not isolated. Convivina bacteria were particularly enriched in the hornet crop and included Convivina intestini, a species adapted towards amino acid metabolism, and Convivina praedatoris sp. nov. which was adapted towards carbohydrate metabolism.
Assuntos
Vespas , Animais , Vespas/genética , RNA Ribossômico 16S/genética , Bactérias/genéticaRESUMO
The genus Agrobacterium was initially described as mainly phytopathogenic strains. Nowadays, the genus includes phytopathogenic and non-phytopathogenic bacteria that are distinctive among the Rhizobiaceae family. Recently we have isolated two closely related strains, LMG 31531T and LMG 31532, from soil and plant roots, respectively. Both strains differ from previously reported species based on the genomic and phenotypic data. A. arsenijevicii KFB 330T and A. fabacearum LMG 31642T showed the highest 16S rRNA similarity (98.9 %), followed by A. nepotum LMG 26435T (98.7 %). A clear genomic feature that distinguishes LMG 31531T and LMG 31532 from other Agrobacterium species is the absence of a linear chromid. Nevertheless, typical values of the core-proteome Average Amino Acid Identity (cpAAI > 85 %) and 16S rRNA gene sequence similarity (>96 %) when compared to other members of the genus confirm the position of these two strains as part of the Agrobacterium genus. They are therefore described as Agrobacterium divergens sp. nov. Besides, our comparative genomic study and survey for clade-specific markers resulted in the discovery of conserved proteins that provide insights into the functional evolution of this genus.
Assuntos
Agrobacterium , Ácidos Graxos , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , DNA Bacteriano/química , Hibridização de Ácido NucleicoRESUMO
BACKGROUND: To understand mechanisms of adaptation and plasticity of pollinators and other insects a better understanding of diversity and function of their key symbionts is required. Commensalibacter is a genus of acetic acid bacterial symbionts in the gut of honey bees and other insect species, yet little information is available on the diversity and function of Commensalibacter bacteria. In the present study, whole-genome sequences of 12 Commensalibacter isolates from bumble bees, butterflies, Asian hornets and rowan berries were determined, and publicly available genome assemblies of 14 Commensalibacter strains were used in a phylogenomic and comparative genomic analysis. RESULTS: The phylogenomic analysis revealed that the 26 Commensalibacter isolates represented four species, i.e. Commensalibacter intestini and three novel species for which we propose the names Commensalibacter melissae sp. nov., Commensalibacter communis sp. nov. and Commensalibacter papalotli sp. nov. Comparative genomic analysis revealed that the four Commensalibacter species had similar genetic pathways for central metabolism characterized by a complete tricarboxylic acid cycle and pentose phosphate pathway, but their genomes differed in size, G + C content, amino acid metabolism and carbohydrate-utilizing enzymes. The reduced genome size, the large number of species-specific gene clusters, and the small number of gene clusters shared between C. melissae and other Commensalibacter species suggested a unique evolutionary process in C. melissae, the Western honey bee symbiont. CONCLUSION: The genus Commensalibacter is a widely distributed insect symbiont that consists of multiple species, each contributing in a species specific manner to the physiology of the holobiont host.
RESUMO
Strain LMG 31809 T was isolated from a top soil sample of a temperate, mixed deciduous forest in Belgium. Comparison of its 16S rRNA gene sequence with that of type strains of bacteria with validly published names positioned it in the class Alphaproteobacteria and highlighted a major evolutionary divergence from its near neighbor species which represented species of the orders Emcibacterales and Sphingomonadales. 16S rRNA amplicon sequencing of the same soil sample revealed a highly diverse community in which Acidobacteria and Alphaproteobacteria predominated, but failed to yield amplicon sequence variants highly similar to that of strain LMG 31809 T. There were no metagenome assembled genomes that corresponded to the same species and a comprehensive analysis of public 16S rRNA amplicon sequencing data sets demonstrated that strain LMG 31809 T represents a rare biosphere bacterium that occurs at very low abundances in multiple soil and water-related ecosystems. The genome analysis suggested that this strain is a strictly aerobic heterotroph that is asaccharolytic and uses organic acids and possibly aromatic compounds as growth substrates. We propose to classify LMG 31809 T as a novel species within a novel genus, Govania unica gen. nov., sp. nov, within the novel family Govaniaceae of the class Alphaproteobacteria. Its type strain is LMG 31809 T (=CECT 30155 T). The whole-genome sequence of strain LMG 31809 T has a size of 3.21 Mbp. The G + C content is 58.99 mol%. The 16S rRNA gene and whole-genome sequences of strain LMG 31809 T are publicly available under accession numbers OQ161091 and JANWOI000000000, respectively.
Assuntos
Alphaproteobacteria , Ácidos Graxos , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Ecossistema , Filogenia , Bactérias/genética , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem BacterianaRESUMO
Belgian lambic beers are still produced through traditional craftsmanship. They rely on a spontaneous fermentation and maturation process that is entirely carried out in wooden barrels. The latter are used repetitively and may introduce some batch-to-batch variability. The present systematic and multiphasic study dealt with two parallel lambic beer productions carried out in nearly identical wooden barrels making use of the same cooled wort. It encompassed a microbiological and metabolomic approach. Further, a taxonomic classification and metagenome-assembled genome (MAG) investigation was based on shotgun metagenomics. These investigations provided new insights into the role of these wooden barrels and key microorganisms for this process. Indeed, besides their role in traditionality, the wooden barrels likely helped in establishing the stable microbial ecosystem of lambic beer fermentation and maturation by acting as an inoculation source of the necessary microorganisms, thereby minimizing batch-to-batch variations. They further provided a microaerobic environment, which aided in achieving the desirable succession of the different microbial communities for a successful lambic beer production process. Moreover, these conditions prevented excessive growth of acetic acid bacteria and, therefore, uncontrolled production of acetic acid and acetoin, which may lead to flavor deviations in lambic beer. Concerning the role of less studied key microorganisms for lambic beer production, it was shown that the Acetobacter lambici MAG contained several acid tolerance mechanisms toward the harsh environment of maturing lambic beer, whereas genes related to sucrose and maltose/maltooligosaccharide consumption and the glyoxylate shunt were absent. Further, a Pediococcus damnosus MAG possessed a gene encoding ferulic acid decarboxylase, possibly contributing to 4-vinyl compound production, as well as several genes, likely plasmid-based, related to hop resistance and biogenic amine production. Finally, contigs related to Dekkera bruxellensis and Brettanomyces custersianus did not possess genes involved in glycerol production, emphasizing the need for alternative external electron acceptors for redox balancing.
Assuntos
Cerveja , Microbiota , Cerveja/microbiologia , Fermentação , Bactérias/genética , PlasmídeosRESUMO
Three forest and four botanical garden top soil isolates with unique MALDI-TOF mass spectra were identified as Paraburkholderia strains closely related to Paraburkholderia sartisoli through recA gene sequence analysis. OrthoANIu, digital DNA-DNA hybridization analyses and phylogenomic analyses demonstrated that the five strains represented two new Paraburkholderia species closely related to P. sartisoli. The genome of strain LMG 31841T had a cumulative size of 6.3 Mb and a G + C content of 62.64 mol%; strain LMG 32171T had a genome size of 5.8 Mb and a G + C content of 62.91 mol%. Hemolysis on horse blood agar, beta-galactosidase and phosphoamidase activity, and assimilation of adipic acid and trisodium citrate allowed phenotypic differentiation of strains LMG 31841T, LMG 32171T and P. sartisoli LMG 24000T. An analysis of the genomic potential for aromatic compound degradation yielded additional differences among strains representing these three species, but also highlighted some discrepancies between the presence of genes and pathways, and the phenotype revealed through growth experiments using a mineral salts medium supplemented with single aromatic compounds as carbon sources. We propose to classify all isolates from the present study into two novel Paraburkholderia species, for which we propose the names Paraburkholderia gardini with LMG 32171T (=CECT 30344T) as the type strain, and Paraburkholderia saeva with LMG 31841T (=CECT 30338T) as the type strain.
Assuntos
Ácidos Graxos , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Florestas , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , SoloRESUMO
We present polyphasic taxonomic data to demonstrate that strain 125703-2019T, a human blood isolate, represents a novel species within the genus Pseudoclavibacter, and to reclassify the illegitimate Zimmermannella alba Lin et al., 2004 as Pseudoclavibacter albus comb. nov. Upon primary isolation, strain 125703-2019T could not be identified reliably using MALDI-TOF mass spectrometry during routine diagnostic work, but partial 16S rRNA gene sequence analysis revealed that it belonged to the genus Pseudoclavibacter. Average nucleotide identity and digital DNA-DNA hybridisation analyses confirmed that it represented a novel species within this genus. A detailed physiological characterisation yielded differential tests between the novel species and its nearest neighbor taxa, which could also be differentiated using MALDI-TOF mass spectrometry. We propose to formally classify this strain into the novel species Pseudoclavibacter triregionum sp. nov., with strain 125703-2019T (= R-76471T, LMG 31777T, CCUG 74796T) as the type strain. The whole-genome assembly of strain 125703-2019T has a size of 2.4 Mb and a G + C content of 72.74%. A Pseudoclavibacter pangenome analysis revealed that 667 gene clusters were exclusively present in strain 125703-2019T. While these gene clusters were enriched in several COG functional categories, this analysis did not reveal functions that explained the occurrence of this species in human infection. Finally, several phylogenetic and phylogenomic analyses demonstrated that the genus Pseudoclavibacter is polyphyletic with Pseudoclavibacter soli and Pseudoclavibacter caeni representing a unique and deeply branching line of descent within the family Microbacteriaceae. We therefore also propose to reclassify both species into the novel genus Caespitibacter gen. nov. as Caespitibacter soli comb. nov. and Caespitibacter caeni comb. nov., respectively, and with C. soli comb. nov. as the type species.
Assuntos
Ácidos Graxos , Técnicas de Tipagem Bacteriana , DNA Bacteriano/química , DNA Bacteriano/genética , Ácidos Graxos/análise , Humanos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
We present genomic, phylogenomic, and phenotypic taxonomic data to demonstrate that three human ear isolates represent a novel species within the genus Gulosibacter. These isolates could not be identified reliably using MALDI-TOF mass spectrometry during routine diagnostic work, but partial 16S rRNA gene sequence analysis revealed that they belonged to the genus Gulosibacter. Overall genomic relatedness indices between the draft genome sequences of the three isolates and of the type strains of established Gulosibacter species confirmed that the three isolates represented a single novel Gulosibacter species. A biochemical characterisation yielded differential tests between the novel and established Gulosibacter species, which could also be differentiated using MALDI-TOF mass spectrometry. We propose to formally classify these three isolates into Gulosibacter hominis sp. nov., with 401352-2018 T (= LMG 31778 T, CCUG 74795 T) as the type strain. The whole-genome sequence of strain 401352-2018 T has a size of 2,340,181 bp and a G+C content of 62.04 mol%. A Gulosibacter pangenome analysis revealed 467 gene clusters that were exclusively present in G. hominis genomes. While these G. hominis specific gene clusters were enriched in several COG functional categories, this analysis did not reveal functions that suggested a role in the human microbiome, nor did it explain the occurrence of G. hominis in ear infections. The absence of acquired antimicrobial resistance determinants and virulence factors in the G. hominis genomes, and an analysis of publicly available 16S rRNA gene sequences and 16S rRNA amplicon sequencing data sets suggested that G. hominis is a member of the human skin microbiota that may occasionally be involved in opportunistic infections.
Assuntos
Microbiota , Infecções Oportunistas , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/análise , Humanos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Gram-negative, aerobic, rod-shaped, non-spore-forming, motile bacteria, designated CBAS 719 T, CBAS 732 and CBAS 720 were isolated from leaf litter samples, collected in Espírito Santo State, Brazil, in 2008. Sequences of the 16S rRNA, gyrB, lepA and recA genes showed that these strains grouped with Burkholderia plantarii LMG 9035 T, Burkholderia gladioli LMG 2216 T and Burkholderia glumae LMG 2196 T in a clade of phytopathogenic Burkholderia species. Digital DNA-DNA hybridization experiments and ANI analyses demonstrated that strain CBAS 719 T represents a novel species in this lineage that is very closely related with B. plantarii. The genome sequence of the type strain is 7.57 Mbp and its G + C content is 69.01 mol%. The absence of growth on TSA medium supplemented with 3% (w/v) NaCl, citrate assimilation, ß-galactosidase (PNPG) activity, and of lipase C14 activity differentiated strain CBAS 719 T from B. plantarii LMG 9035 T, its nearest phylogenetic neighbor. Its predominant fatty acid components were C16:0, C18:1 ω7c, cyclo-C17:0 and summed feature 3 (C16:1 ω7c and/or C15:0 iso 2-OH). Based on these genotypic and phenotypic characteristics, the strains CBAS 719 T, CBAS 732 and CBAS 720 are classified in a novel Burkholderia species, for which the name Burkholderia perseverans sp. nov. is proposed. The type strain is CBAS 719 T (= LMG 31557 T = INN12T).
Assuntos
Antibiose , Burkholderia , Ecossistema , Agaricales/efeitos dos fármacos , Agaricales/fisiologia , Antibiose/fisiologia , Aspergillus/efeitos dos fármacos , Aspergillus/fisiologia , Técnicas de Tipagem Bacteriana , Brasil , Burkholderia/química , Burkholderia/classificação , Burkholderia/genética , DNA Bacteriano/genética , Fosfolipídeos/análise , Filogenia , Phytophthora/efeitos dos fármacos , Phytophthora/fisiologia , Folhas de Planta/microbiologia , RNA Ribossômico 16S/genética , Especificidade da Espécie , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/farmacologiaRESUMO
Two Gram-negative, aerobic, rod-shaped and yellow-orange pigmented bacterial strains (LMG 31523T and LMG 31524) were isolated from roots of wild-growing Alkanna tinctoria plants collected near Thessaloniki, Greece. Analysis of their 16S rRNA gene sequences revealed that they form a separate cluster related to the genus Roseomonas. A comparative whole genome analysis of the two strains and the type strains of related Roseomonas species revealed average nucleotide identity values from 78.84 and 80.32%. The Gâ¯+â¯C contents of the genomic DNA of strains LMG 31523T and LMG 31524 were 69.69% and 69.74%, respectively. Combined data from phenotypic, phylogenetic and chemotaxonomic studies indicated that the strains LMG 31523T and LMG 31524 represent a novel species of the genus Roseomonas. Genome analysis of the new strains showed a number of genes involved in survival in the rhizosphere environment and in plant colonization and confirmed the endophytic characteristics of LMG 31523T and LMG 31524. Since the strains LMG 31523T and LMG 31524 were isolated from a plant collected in Greece the name Roseomonas hellenica sp. nov. is proposed. The type strain is LMG 31523T (=CECT 30032T).
Assuntos
Boraginaceae , Methylobacteriaceae , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Boraginaceae/microbiologia , DNA Bacteriano/genética , Endófitos , Grécia , Methylobacteriaceae/classificação , Methylobacteriaceae/isolamento & purificação , Pigmentação , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Six endospore-forming, Gram-stain-positive or variable, motile, rod-shaped, aerobic or facultatively anaerobic bacteria with different MALDI-TOF mass spectra (MS) were isolated from the phyllosphere of Arabidopsis thaliana plants grown in plant chambers after inoculation of surface sterilized seeds with a top soil microbial cell suspension. They were identified as members of the genus Paenibacillus through comparison with a commercial MALDI-TOF MS database and comparative 16S rRNA gene sequencing. Their genome sequences comprised multiple biosynthetic gene clusters and suggested they have unexplored biotechnological potential. Analyses of average nucleotide identity values between these strains and the type strains of their nearest neighbour species demonstrated that they represented a novel Paenibacillus species each. A detailed phenotypic comparison yielded distinctive biochemical characteristics for each of these novel species. We therefore propose to classify that these isolates into six novel species within genus Paenibacillus, for which we propose the names Paenibacillus foliorum sp. nov., Paenibacillus phytohabitans sp. nov., Paenibacillus plantarum sp. nov., Paenibacillus planticolens sp. nov., Paenibacillus phytorum sp. nov. and Paenibacillus germinis sp. nov., with strains LMG 31456T (=R-74617T=CECT 30138T), LMG 31459T (=R-74621T=CECT 30135T), LMG 31461T (=R-74618T=CECT 30133T), LMG 31457T (=R-74619T=CECT 30137T), LMG 31458T (=R-74620T=CECT 30136T) and LMG 31460T (=R-74622T=CECT 30134T) as the type strains, respectively.
Assuntos
Arabidopsis/microbiologia , Paenibacillus/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Paenibacillus/isolamento & purificação , Folhas de Planta/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Dromedary camel milk is generally considered a valuable and marketable commodity but its production suffers from poor hygienic conditions that result in low microbiological quality and the presence of various pathogens. The objective of the present study was to provide a detailed report of the bacterial species level composition of Moroccan raw camel milk samples that can serve as a starting point for the selection of starter cultures to facilitate a change in manufacturing practices to an improved and safer production system. The composition of the bacterial community in four freshly collected raw camel milk samples was analyzed by performing a large-scale isolation campaign combined with 16S rRNA gene amplicon sequencing. A total of 806 isolates were obtained from four raw camel milk samples using ten combinations of growth media and incubation conditions. Subsequent isolate dereplication using MALDI-TOF mass spectrometry and identification of representative isolates through sequence analysis of protein encoding and 16S rRNA genes revealed the presence of established and novel dairy lactic acid bacteria, as well as bacteria that are considered indicators of poor hygienic conditions and psychrotrophic spoilage organisms. The large numbers of Lactococcus and Enterococcus isolates obtained present an interesting resource for starter culture selection.
Assuntos
Bactérias/isolamento & purificação , Camelus/fisiologia , Enterococcus/isolamento & purificação , Leite/microbiologia , Alimentos Crus/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Enterococcus/genética , Microbiologia de Alimentos , Lactobacillales/genética , Lactobacillales/isolamento & purificação , Marrocos , RNA Ribossômico 16S/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
A diverse set of bacteria live on the above-ground parts of plants, composing the phyllosphere, and play important roles for plant health. Phyllosphere microbial communities assemble in a predictable manner and diverge from communities colonizing other plant organs or the soil. However, how these communities differ functionally remains obscure. We assembled a collection of 258 bacterial isolates representative of the most abundant taxa of the phyllosphere of Arabidopsis and a shared soil inoculum. We screened the collection for the production of metabolites that inhibit the growth of Gram-positive and Gram-negative bacteria either in isolation or in co-culture. We found that isolates capable of constitutive antibiotic production in monoculture were significantly enriched in the soil fraction. In contrast, the proportion of binary cultures resulting in the production of growth inhibitory compounds differed only marginally between the phyllosphere and soil fractions. This shows that the phyllosphere may be a rich resource for potentially novel molecules with antibiotic activity, but that production or activity is dependent upon induction by external signals or cues. Finally, we describe the isolation of antimicrobial acyloin metabolites from a binary culture of Arabidopsis phyllosphere isolates, which inhibit the growth of clinically relevant Acinetobacter baumannii.
Assuntos
Antibacterianos , Arabidopsis , Antibacterianos/farmacologia , Bactérias/genética , Técnicas de Cocultura , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Folhas de PlantaRESUMO
A phylogenomic analysis based on 107 single-copy core genes revealed that three strains from sugar-rich environments, i.e. LMG 1728T, LMG 1731 and LMG 22058, represented a single, novel Gluconacetobacter lineage with Gluconacetobacter liquefaciens as nearest validly named neighbour. OrthoANIu and digital DNA-DNA hybridization analyses among these strains and Gluconacetobacter type strains confirmed that the three strains represented a novel Gluconacetobacter species. Biochemical characteristics and MALDI-TOF mass spectra allowed differentiation of this novel species from the type strains of G. liquefaciens and other closely related Gluconacetobacter species. We therefore propose to classify strains LMG 1728T, LMG 1731 and LMG 22058 in the novel species Gluconacetobacter dulcium sp. nov., with LMG 1728T (=CECT 30142T) as the type strain.