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1.
Braz. j. oral sci ; 21: e224809, jan.-dez. 2022. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1354721

RESUMO

Aim: The aim of the present study was to evaluate the microbial contamination in internal and external walls of cone morse implant walls. Methods: Eleven patients with edentulous mandibular posterior area were selected to received dental implants, divided into groups: submerged (S), non-submerged (NS), and immediately loaded (IL). Microbiological evaluations (microorganisms' number, aerobic and anaerobic colony forming units (CFU) number and microorganisms' qualification) were divided into internal and external collection of the implant walls, at different stages: T0 (surgical procedure), T2 (suture removal), T4 (reopening S group), T6 (suture removal S group), and T8 (abutment placement in S and NS). All data were submitted to statistical analyses, with confidence level of 0.05. Results: There was difference in number of microorganisms observed over time within the same group (p < 0.05). A difference was observed in CFU when evaluated within the same group over time (p < 0.05), except for the IL group. In internal collection, a predominance of non-formation of microorganisms was observed at T0 in all groups, while formation of Gram-positive Diplococci and Gram-positive Bacilli was observed at T8 (p>0.05). In external collection, an increase in number of microorganisms was observed at T0. Conclusion: There was no difference in microbial contamination among the evaluated groups. The microorganism's colonization changed over time


Assuntos
Humanos , Masculino , Feminino , Cirurgia Bucal , Implantes Dentários , Actinobacteria
2.
Sci Rep ; 12(1): 15502, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109598

RESUMO

Gulosibacter molinativorax ON4T is the only known organism to produce molinate hydrolase (MolA), which catalyses the breakdown of the thiocarbamate herbicide into azepane-1-carboxylic acid (ACA) and ethanethiol. A combined genomic and transcriptomic strategy was used to fully characterize the strain ON4T genome, particularly the molA genetic environment, to identify the potential genes encoding ACA degradation enzymes. Genomic data revealed that molA is the only catabolic gene of a novel composite transposon (Tn6311), located in a novel low copy number plasmid (pARLON1) harbouring a putative T4SS of the class FATA. pARLON1 had an ANI value of 88.2% with contig 18 from Agrococcus casei LMG 22410T draft genome. Such results suggest that pARLON1 is related to genomic elements of other Actinobacteria, although Tn6311 was observed only in strain ON4T. Furthermore, genomic and transcriptomic data demonstrated that the genes involved in ACA degradation are chromosomal. Based on their overexpression when growing in the presence of molinate, the enzymes potentially involved in the heterocyclic ring breakdown were predicted. Among these, the activity of a protein related to caprolactone hydrolase was demonstrated using heterologous expression. However, further studies are needed to confirm the role of the other putative enzymes.


Assuntos
Actinomycetales , Herbicidas , Actinobacteria , Actinomycetales/genética , Azepinas , Herbicidas/metabolismo , Hidrolases/genética , Hidrolases/metabolismo , Tiocarbamatos
3.
Arch Microbiol ; 204(10): 643, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36156742

RESUMO

A novel actinobacterium, designated strain HDS12T, was isolated from fruits collected from Changde city located in the northwest of Hunan Province, China and characterized using a polyphasic approach. The 16S rRNA gene sequence analysis indicated that strain HDS12T belonged to the genus Nocardiopsis, and had highest similarities to N. dassonvillei subsp. dassonvillei CGMCC 4.1231T (99.79%), N. deserti H13T (99.73%), N. alborubida NBRC 13392T (99.66%), N. dassonvillei subsp. crassaminis D1T (99.64%), N. synnemataformans DSM 44143T (99.45%), N. lucentensis DSM 44048T (99.04%), N. aegyptia DSM 44442T (98.90%), N. flavescens CGMCC 4.5723T (98.76%), N. alba DSM 43377T (98.69%) and N. halotolerans DSM 44410T (98.63%), respectively. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain HDS12T formed an independent subclade, suggesting that strain HDS12T could belong to a potential novel species. Phylogenomic analysis demonstrated that strain HDS12T was closely related to N. dassonvillei subsp. dassonvillei CGMCC 4.1231T and N. dassonvillei subsp. crassaminis D1T. However, the average nucleotide identity value and the digital DNA-DNA hybridization value between them were well below 95-96% and 70% cut-off point recommended for delineating species. Based on its phenotypic and chemotaxonomic characteristics, strain HDS12T (= MCCC 1K06173T = JCM 34708T) represents the type strain of a novel species, for which the name Nocardiopsis akebiae sp. nov. is proposed.


Assuntos
Actinobacteria , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Frutas/química , Nocardiopsis , Nucleotídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
4.
Int J Mol Sci ; 23(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36142829

RESUMO

Diseases caused by the Gram-positive bacterium Curtobacteriumflaccumfaciens pv. flaccumfaciens (Cff) inflict substantial economic losses in soybean cultivation. Use of specific bacterial viruses (bacteriophages) for treatment of seeds and plants to prevent the development of bacterial infections is a promising approach for bioprotection in agriculture. Phage control has been successfully tested for a number of staple crops. However, this approach has never been applied to treat bacterial diseases of legumes caused by Cff, and no specific bacteriophages have been known to date. This paper presents detailed characteristics of the first lytic bacteriophage infecting this pathogen. Phage Ayka, related to φ29-like (Salasmaviridae) viruses, but representing a new subfamily, was shown to control the development of bacterial wilt and tan spot in vitro and in greenhouse plants.


Assuntos
Actinomycetales , Infecções Bacterianas , Bacteriófagos , Fabaceae , Actinobacteria , Bactérias , Fabaceae/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Soja
5.
Int J Mol Sci ; 23(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36142891

RESUMO

The bile resistance of intestinal bacteria is among the key factors responsible for their successful colonization of and survival in the mammalian gastrointestinal tract. In this study, we demonstrated that lactate-producing Atopobiaceae bacteria (Leptogranulimonas caecicola TOC12T and Granulimonas faecalis OPF53T) isolated from mouse intestine showed high resistance to mammalian bile extracts, due to significant bile salt hydrolase (BSH) activity. We further succeeded in isolating BSH proteins (designated LcBSH and GfBSH) from L. caecicola TOC12T and G. faecalis OPF53T, respectively, and characterized their enzymatic features. Interestingly, recombinant LcBSH and GfBSH proteins exhibited BSH activity against 12 conjugated bile salts, indicating that LcBSH and GfBSH have much broader substrate specificity than the previously identified BSHs from lactic acid bacteria, which are generally known to hydrolyze six bile salt isomers. Phylogenetic analysis showed that LcBSH and GfBSH had no affinities with any known BSH subgroup and constituted a new BSH subgroup in the phylogeny. In summary, we discovered functional BSHs with broad substrate specificity from Atopobiaceae bacteria and demonstrated that these BSH enzymes confer bile resistance to L. caecicola TOC12T and G. faecalis OPF53T.


Assuntos
Actinobacteria , Lactobacillales , Actinobacteria/metabolismo , Amidoidrolases/metabolismo , Animais , Bile/metabolismo , Ácidos e Sais Biliares , Lactatos , Lactobacillales/metabolismo , Mamíferos/metabolismo , Camundongos , Filogenia , Especificidade por Substrato
6.
Nutrients ; 14(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36145169

RESUMO

The microbiota-gut-brain axis extends beyond visceral perception, influencing higher-order brain structures, and ultimately psychological functions, such as fear processing. In this exploratory pilot study, we attempted to provide novel experimental evidence of a relationship between gut microbiota composition and diversity, and fear-processing in obesity, through a behavioral approach. Women affected by obesity were enrolled and profiled for gut microbiota, through 16S rRNA amplicon sequencing. Moreover, we tested their ability to recognize facial fearful expressions through an implicit-facial-emotion-recognition task. Finally, a traditional self-report questionnaire was used to assess their temperamental traits. The participants exhibited an unbalanced gut microbiota profile, along with impaired recognition of fearful expressions. Interestingly, dysbiosis was more severe in those participants with altered behavioral performance, with a decrease in typically health-associated microbes, and an increase in the potential pathobiont, Collinsella. Moreover, Collinsella was related to a lower expression of the persistence temperamental trait, while a higher expression of the harm-avoidance temperament, related to fear-driven anxiety symptoms, was linked to Lactobacillus. Once confirmed, our findings could pave the way for the design of innovative microbiome-based strategies for the treatment of psychological and emotional difficulties by mitigating obesity-related consequences and behaviors.


Assuntos
Actinobacteria , Microbioma Gastrointestinal , Actinobacteria/genética , Disbiose , Medo , Fezes , Feminino , Microbioma Gastrointestinal/genética , Humanos , Obesidade/metabolismo , Projetos Piloto , RNA Ribossômico 16S/genética
7.
Arch Microbiol ; 204(10): 641, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149504

RESUMO

Actinomycetes are filamentous bacteria and the residents of the soil, prone to produce bioactive metabolites. This research aimed to isolate, classify, and investigate the anticancer properties of Actinomycetes secondary metabolites from various saline soils of Qom province. Actinomycetes isolates were molecularly recognized by 16SrRNA gene sequencing after the PCR procedure. The A549 cell line was then exposed to bacterial metabolites to find their cytotoxicity by MTT assay and their capacity to cause apoptosis by Flow cytometry. The expression levels of the bax and bcl-2 genes were determined using Real-time PCR. Bacterial metabolites were distinct by HPLC and GC-MS assays. Sequencing identified three novel Actinomycetes strains, Streptomyces griseoflavus, Streptomyces calvus, and Kitasatospora phosalacineus. The IC50 doses of bacterial metabolites were discovered equal to 1337, 2619, and 4874 µg/ml, respectively. Flow cytometric assay revealed that their secondary metabolites were capable of inducing apoptosis in A549 cells by 25%, 14.5%, and 7.58%, respectively. Real-time PCR findings displayed that the bax gene expression in A549 cells treated with S. griseoflavus and S. calvus, comparatively increased (P < 0.0008, P < 0.00056). The expression of the bcl-2 gene was significantly reduced in cells treated with S. griseoflavus and K. phosalacineus (P < 0.0006, P < 0.0004). The findings of this analysis showed the presence of new isolates in a soil sample from Qom province which can produce new anticancer agents and can be considered appropriate candidates for further research to employ as anticancer drugs.


Assuntos
Actinobacteria , Antineoplásicos , Células A549 , Actinomyces , Humanos , Solo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Extremophiles ; 26(3): 30, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149604

RESUMO

Chromium is one of the most widely used metals in industry. Hexavalent form [Cr(VI)], which is found in industrial discharges, is very toxic and very soluble in water. From soil taken from an abandoned lead and iron mine, a bacterial strain capable of reducing Cr(VI) was isolated and identified as Brachybacterium paraconglomeratum ER41. Objective of this work was to evaluate the power of this bacterium to reduce Cr(VI). Results obtained showed that this bacterium is capable of eliminating 100 mg/L of Cr(VI) after 48 h (pH 8 and temperature 30 °C). For modeling biosorption kinetics, pseudo-first-order and intraparticle diffusion models gave a better fit. Furthermore, the adsorption mechanism conformed well to Langmuir's isothermal model indicating monolayer type sorption. Biomass analysis of this bacterium before and after contact with chromium by scanning electron microscopy-energy-dispersive X-ray and by Fourier transform infrared spectroscopy showed that the surface ligands of bacterial wall are probably responsible for biosorption and bioreduction process. These results suggest a potential application of B. paraconglomeratum ER41 in bioremediation of polluted discharges.


Assuntos
Poluentes Químicos da Água , Actinobacteria , Bactérias , Cromo/química , Concentração de Íons de Hidrogênio , Ferro , Cinética , Ligantes , Solo , Água
9.
Biomed Pharmacother ; 153: 113518, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36076603

RESUMO

OBJECTIVE: To analyze the gut microbiota of patients with rheumatoid arthritis (RA) according to disease activity. METHODS: An observational cross-sectional study of 110 patients with RA and 110 age- and sex-matched controls was performed. Patients were classified according to the disease activity (DAS28 ≥3.2 or DAS28 <3.2). Clinical and epidemiological variables were included. The gut microbiota was analyzed using 16S rRNA sequencing and bioinformatics analysis based on QIIME and PICRUSt. A multivariate analysis was performed to identify factors associated with inflammatory activity. RESULTS: The mean DAS28 indicated remission/low inflammatory activity in 71 patients (64.5 %) and moderate/high activity in 39 (35.5 %) during follow-up. Alpha and beta diversity analysis revealed differences in gut microbiota between the 3 study groups. In the moderate/high activity RA, we observed a significant change in the abundance of genera compared with the other groups. The abundance of Collinsella and Bifidobacterium was increased in RA patients compared with controls. The metabolic profile of gut microbiota was characterized by differences in pathways related to Biosynthesis, Generation of Precursor Metabolites/Energy, and Degradation/Utilization/Assimilation between the 3 groups. The factors associated with cumulative inflammatory activity in RA were age (OR [95 % CI], 1.065 [1.002-1.131]), obesity (OR [95% CI], 3.829 [1.064-8.785]), HAQ score (OR [95% CI], 2.729 [1.240-5.009]), and expansion of the genus Collinsella (OR [95% CI], 3.000 [1.754-9.940]). CONCLUSIONS: The composition of gut microbiota differed between patients with RA and moderate/high activity, patients with remission/low activity, and controls. The genus Collinsella, age, obesity, and physical function were associated with cumulative inflammatory burden in RA.


Assuntos
Actinobacteria , Artrite Reumatoide , Estudos de Coortes , Estudos Transversais , Humanos , Obesidade , RNA Ribossômico 16S/genética
10.
J Environ Manage ; 320: 115870, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36056489

RESUMO

Biopurification systems (BPS) or biobeds are bioprophylaxis systems to prevent pesticide point-source contamination, whose efficiency relies mostly on the pesticide removal capacity of the biomixture, the majority component of a BPS. The adaptation of the components of the biomixtures to local availabilities is a key aspect to ensure the sustainability of the system. In this work, the removal of atrazine (ATZ) was evaluated in biomixtures formulated with three sugarcane by-products as alternative lignocellulosic substrates. Based on the capacity of actinobacteria to tolerate and degrade diverse pesticides, the effect of biomixtures bioaugmentation with actinobacteria was evaluated as a strategy to enhance the depuration capacity of biobeds. Also, the effect of ATZ and/or the bioaugmentation on microbial developments and enzymatic activities were studied. The biomixtures formulated with bagasse, filter cake, or harvest residue, reached pesticide removal values of 37-41% at 28 d of incubation, with t1/2 between 37.9 ± 0.4 d and 52.3 ± 0.4 d. The bioaugmentation with Streptomyces sp. M7 accelerated the dissipation of the pesticide in the biomixtures, reducing ATZ t1/2 3-fold regarding the controls, and achieving up to 72% of ATZ removal. Atrazine did not exert a clear effect on microbial developments, although most of the microbial counts were less in the contaminated biomixtures at the end of the assay. The bioaugmentation improved the development of the microbiota in general, specially actinobacteria and fungi, regarding the non-bioaugmented systems. The inoculation with Streptomyces sp. M7 enhanced acid phosphatase activity and/or reversed a possible effect of the pesticide over this enzymatic activity.


Assuntos
Actinobacteria , Atrazina , Praguicidas , Poluentes do Solo , Streptomyces , Actinobacteria/metabolismo , Atrazina/metabolismo , Biodegradação Ambiental , Solo/química , Poluentes do Solo/metabolismo , Streptomyces/metabolismo
11.
J Antibiot (Tokyo) ; 75(10): 542-551, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36071213

RESUMO

A bisprenyl naphthoquinone, phytohabinone (1), and a calcimycin congener with unusual modifications, phytohabimicin (2), were isolated from the culture extract of Phytohabitans sp. RD003013. The structures of 1 and 2 were determined by NMR and MS analyses, and the absolute configuration of 2 was established by using electronic circular dichroism (ECD) calculation. The prenylation pattern of 1 was unprecedented among the known prenylated naphthoquinones. Compound 2 represents a spiroacetal core of polyketide origin substituted with a thiazole carboxylic acid and a dichrolopyrrole moiety, which is an unprecedented modification pattern in the known calcimycin family natural products. Remarkably, 2 showed moderate antimicrobial activity against a Gram-negative bacterium Ralstonia solanacearum while calcimycin was inactive. Additionally, 2 inhibits the migration of EC17 cancer cells at noncytotoxic concentrations.


Assuntos
Actinobacteria , Micromonosporaceae , Naftoquinonas , Calcimicina , Estrutura Molecular , Naftoquinonas/química , Tiazóis
12.
J Antibiot (Tokyo) ; 75(10): 535-541, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36071214

RESUMO

In the course of our screening program for new anti-methicillin-resistant Staphylococcus aureus antibiotics, four novel antibiotics, termed wychimicins A-D, were isolated from the culture broth of the rare actinomycete Actinocrispum wychmicini strain MI503-AF4. Wychimicins are spirotetronates possessing a macrocyclic 13-membered ring containing trans-decalin and ß-D-xylo-hexopyranose moieties connected to C-17 by an O-glycosidic linkage according to MS, NMR and X-ray analyses. In X-ray crystal structure analysis, the Flack constant was 0.10 (11). The stereochemistry of the spirocarbon C-25 was R. Wychimicins had a minimum inhibitory concentration of 0.125-2 µg ml-1 against methicillin-resistant Staphylococcus aureus.


Assuntos
Actinobacteria , Actinomycetales , Staphylococcus aureus Resistente à Meticilina , Policetídeos , Antibacterianos/química , Testes de Sensibilidade Microbiana
13.
ACS Chem Biol ; 17(9): 2664-2672, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36074093

RESUMO

To investigate the potential for secondary metabolite biosynthesis by Streptomyces species, we employed a coculture method to discover natural bioactive products and identified specific antibacterial activity from a combined-culture of Streptomyces hygroscopicus HOK021 and Tsukamurella pulmonis TP-B0596. Molecular networking using ultrahigh performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS) data revealed a specific clade of metabolites in this combined-culture that were not detected in both monocultures. Using the chemical profiles, a previously unidentified conjugate between FabF inhibitor and catechol-type siderophore was successfully identified and named harundomycin A. Harundomycin A was a conjugate between the 2,4-dihydroxy-3-aminobenzoate moiety of platensimycin and N,N'-bis(2,3-dihydroxybenzoyl)-O-seryl-cysteine (bisDHBA-Ser-Cys) with a thioester linkage. Along with the production of harundomycin A, platensimycin, its thiocarboxylic acid form thioplatensimycin, enterobactin, and its degradation product N,N'-bis(2,3-dihydroxybenzoyl)-O-l-seryl-dehydroalanine (bisDHBA-Ser-Dha) were also induced in the combined-culture. Genomic data of S. hygroscopicus HOK021 and T. pulmonis TP-B0596 indicated that strain HOK021 possessed biosynthetic gene clusters for both platensimycin and enterobactin, and thereby revealed that T. pulmonis stimulates HOK021 and acts as an inducer of both of these metabolites. Although the harundomycin A was modified by bulky bisDHBA-Ser-Cys, responsible for the binding to the target molecule FabF, it showed a similar antibacterial spectrum to platensimycin, including against methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, suggesting that the pharmacophore is platensimycin. Additionally, Chrome Azurol S assay showed that harundomycin A possesses ferric iron-chelating activity comparable to that of enterobactin. Our study demonstrated the transformation of existing natural products to bifunctional molecules driven by bacterial interaction.


Assuntos
Produtos Biológicos , Staphylococcus aureus Resistente à Meticilina , Streptomyces , Actinobacteria , Adamantano , Aminobenzoatos , Anilidas , Antibacterianos/química , Produtos Biológicos/metabolismo , Catecóis/metabolismo , Cisteína/metabolismo , Enterobactina/metabolismo , Sideróforos/metabolismo , Streptomyces/metabolismo , Espectrometria de Massas em Tandem , meta-Aminobenzoatos/metabolismo
15.
Front Cell Infect Microbiol ; 12: 789436, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051241

RESUMO

To describe microbiota profiles considering potential influencing factors in pre-school children with recurrent respiratory tract infections (rRTIs) and to evaluate microbiota changes associated with oral bacterial lysate OM-85 treatment, we analyzed gut and nasopharynx (NP) microbiota composition in patients included in the OM-85-pediatric rRTIs (OMPeR) clinical trial (https://www.clinicaltrialsregister.eu/ctr-search/trial/2016-002705-19/IT). Relative percentage abundance was used to describe microbiota profiles in all the available biological specimens, grouped by age, atopy, and rRTIs both at inclusion (T0) and at the end of the study, after treatment with OM-85 or placebo (T1). At T0, Firmicutes and Bacteriodetes were the predominant genera in gut and Proteobacteria, Firmicutes, and Actinobacteria were the predominant genera in NP samples. Gut microbiota relative composition differed with age (<2 vs. ≥2 years) for Firmicutes, Proteobacteria, Actinobacteria (phyla) and Bifidobacterium, Ruminococcus, Lachnospiraceae (genera) (p < 0.05). Moraxella was more enriched in the NP of patients with a history of up to three RTIs. Intra-group changes in relative percentage abundance were described only for patients with gut and NP microbiota analysis available at both T0 and T1 for each study arm. In this preliminary analysis, the gut microbiota seemed more stable over the 6-month study in the OM-85 group, whose mean age was lower, as compared to the placebo group (p = 0.004). In this latter group, the relative abundance of Bacteroides decreased significantly in children ≥2 years. Some longitudinal significant differences in genera relative abundance were also detected in children of ≥2 years for NP Actinobacteria, Haemophilus, and Corynebacterium in the placebo group only. Due to the small number of patients in the different sub-populations, we could not identify significant differences in the clinical outcome and therefore no associations with microbiota changes were searched. The use of bacterial lysates might play a role in microbiota rearrangement, but further data and advanced analysis are needed to prove this in less heterogeneous populations with higher numbers of samples considering the multiple influencing factors such as delivery method, age, environment, diet, antibiotic use, and type of infections to ultimately show any associations with prevention of rRTIs.


Assuntos
Actinobacteria , Microbioma Gastrointestinal , Infecções Respiratórias , Bactérias/genética , Extratos Celulares , Pré-Escolar , Firmicutes , Humanos , Lactente , Proteobactérias
16.
Artigo em Inglês | MEDLINE | ID: mdl-35939329

RESUMO

A novel Gram-stain-positive, aerobic, non-motile and rod-shaped bacterium, designated strain NC76-1T, was isolated from soil from a field that had undergone seven years continuous maize cropping from Liuba town located in Zhangye city, Gansu province, PR China. Colonies of strain NC76-1T were white, opaque and circular with a convex shape. The isolate was found to be able to grow at 10-40 °C (optimum 30 °C), pH 6.0 to 12.0 (optimum 7.0-8.0) and with 0-5.0 % (w/v) NaCl (optimum 0%). On the basis of the results of 16S rRNA gene sequence analysis, the strain fell within the clade of the genus Leucobacter, showing the highest sequence similarities with Leucobacter iarius 40T (97.4%), Leucobacter aridicollis CIP 108388T (97.0%), Leucobacter chromiireducens subsp. solipictus TAN 31504T (96.7%) and Leucobacter denitrificans M1T8B10T (96.7%). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between NC76-1T and its closest relatives, L. iarius 40T, L. aridicollis CIP 108388T, L. chromiireducens subsp. solipictus TAN 31504T and L. denitrificans M1T8B10T were ≤73.5 % and 20.3%, respectively. The genomic DNA G+C content of NC76-1T was 61.5 mol%. It presented MK-11 as the predominant menaquinone. The major cellular fatty acids were anteiso-C15 : 0 (49.2 %) and iso-C16 : 0 (35.7%). The major polar lipids were found to be diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, aminoglycolipid, five glycolipid and one unidentified lipids. The cell wall amino acids were 2,4-diaminobutyric acid, alanine, glutamic acid, glycine and threonine. On the basis of the phylogenetic, phenotypic and chemotaxonomic characteristics, strain NC76-1T is concluded to represent a novel species within the genus Leucobacter, for which the name Leucobacter chinensis sp. nov. is proposed. The type strain is NC76-1T (GDMCC 1.2286T= JCM 34651T).


Assuntos
Actinomycetales , Zea mays , Actinobacteria , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo , Triacetonamina-N-Oxil
17.
Huan Jing Ke Xue ; 43(8): 4342-4352, 2022 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-35971730

RESUMO

In order to investigate the characteristics of soil microbial community structure and their relationships with environmental factors in the surrounding farmlands of a mercury mining region, we analyzed soil physical and chemical properties, Hg pollution, enzyme activity, and microbial community structure characteristics in the surrounding farmlands of a mercury mining region in Tong Ren (Bahuang Town, Bijiang District; Huaqiao Town, Shiqian County; Kaide Town, Jiangkou County; and Chuantong town, Bijiang District; referred to as BJ, SQ, JK, and TR, respectively). The relationships between the characteristics of soil microbial community structure and environmental factors were determined using redundancy analysis (RDA) and correlation network analysis. The results showed that the degree of soil Hg contamination varied depending on the sampling locations in the study region. The soils in JK and TR were categorized as having light-level Hg contamination, whereas those in SQ and BJ were at moderate-level Hg contamination. The potential ecological risk indicated that the soil suffered different degrees of Hg contamination (TR was at a medium level, BJ and JK were at a serious level, and SQ was at a high severe level of pollution). The dominant bacteria flora were Proteobacteria, Actinobacteria, Acidobacteria, and Chloroflexi, whereas the dominant flora of fungi included Ascomycota, Basidiomycota, and Mortierellomycota. RDA analysis showed that pH, sucrase (SC), and catalase (CAT) activities were the key environmental factors of soil bacterial community structure. Soil pH, available nitrogen (AN), available potassium (AK), HCl-Hg, acid phosphatase (ACP), and urease (URE) activities were the key environmental factors that affected soil fungal community structure. Correlation network analysis indicated that pH, available phosphorus (AP), HCl-Hg, SC, ACP, and CAT were the key environmental factors affecting soil bacterial community structure, including Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, Firmicutes, Rokubacteria, and Planctomycetes. AK, pH, total nitrogen (TN), AP, AN, ACP, URE, and SC activities were the key environmental factors affecting soil fungal community structure, such as Ascomycota, Basidiomycota, Mortierellomycota, Glomeromycota, Chytridiomycota, Rozellomycota, Kickxellomycota, and Mucoromycota.


Assuntos
Actinobacteria , Mercúrio , Microbiota , Acidobacteria , Bactérias , Fazendas , Fungos , Mineração , Nitrogênio , Proteobactérias , Solo/química , Microbiologia do Solo
18.
Nat Commun ; 13(1): 5044, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36028509

RESUMO

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are structurally complex natural products with diverse bioactivities. Here we report discovery of a RiPP, kintamdin, for which the structure is determined through spectroscopy, spectrometry and genomic analysis to feature a bis-thioether macrocyclic ring and a ß-enamino acid residue. Biosynthetic investigation demonstrated that its pathway relies on four dedicated proteins: phosphotransferase KinD, Lyase KinC, kinase homolog KinH and flavoprotein KinI, which share low homologues to enzymes known in other RiPP biosynthesis. During the posttranslational modifications, KinCD is responsible for the formation of the characteristic dehydroamino acid residues including the ß-enamino acid residue, followed by oxidative decarboxylation on the C-terminal Cys and subsequent cyclization to provide the bis-thioether ring moiety mediated by coordinated action of KinH and KinI. Finally, conserved genomic investigation allows further identification of two kintamdin-like peptides among the kin-like BGCs, suggesting the occurrence of RiPPs from actinobacteria.


Assuntos
Actinobacteria , Produtos Biológicos , Peptídeos , Processamento de Proteína Pós-Traducional , Sulfetos
19.
Artigo em Inglês | MEDLINE | ID: mdl-36018780

RESUMO

A novel actinobacterium, designated KC 17012T, was isolated from lead zinc tailings collected from Lanping, Yunnan, PR China. Comparative 16S rRNA gene sequencing showed that KC 17012T belonged to the genus Streptomyces and was most closely related to the type strains of Streptomyces neyagawaensis (98.34%), Streptomyces panaciradicis (98.34%) and Streptomyces heilongjiangensis (98.27%). Phylogenetic tree analysis revealed strain KC 17012T formed a distinct clade. The genome size was 8.64 Mbp with a DNA G+C content of 70.8%. Digital DNA-DNA hybridization and average nucleotide identity values between the genome sequence of strain KC 17012T and those of S. neyagawaensis JCM 4796T (25.3 and 81.5 %) and S. panaciradicis NBRC 109811T (30.1 and 85.7 %) were below the thresholds of 70 and 96% for prokaryotic conspecific assignation. The strain formed long straight aerial hyphae which generated regular short rod spores with spiny surfaces. Growth occurred at 10-45 °C, pH 6-8 and with 0-9 % NaCl (w/v). Strain KC 17012T contained ll-diaminopimelic acid and the major whole-cell hydrolysates included glucose, mannose and ribose. The menaquinones were MK-9(H4), MK-9(H6) and MK-9(H8). The major cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, one unidentified lipid and one unidentified phospholipid. On the basis of the results of a polyphasic taxonomic study, it is concluded that KC 17012T represents a novel species of the genus Streptomyces, for which the name Streptomyces plumbidurans sp. nov., is proposed. The type strain is KC 17012T (CGMCC 4.7704T=JCM 35204T).


Assuntos
Actinobacteria , Streptomyces , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Chumbo , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2
20.
J Microbiol ; 60(10): 977-985, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35984616

RESUMO

Two strictly aerobic, Gram-staining-positive, non-spore-forming, regular rod-shaped (approximately 0.7 × 1.9 mm) bacteria (HY170T and HY001) were isolated from bat feces collected from Chongzuo city, Guangxi province (22°20'54″N, 106°49'20″E, July 2011) and Chuxiong Yi Autonomous Prefecture, Yunnan province (25°09'10″N, 102°04'39″E, October 2013) of South China, respectively. Optimal growth is obtained at 25-28°C (range, 4-32°C) on BHI-5% sheep blood plate with pH 7.5 (range, 5.0-10.0) in the presence of 0.5-1.0% NaCl (w/v) (range, 0-15% NaCl [w/v]). The phylogenetic and phylogenomic trees based respectively on the 16S rRNA gene and 845 core gene sequences revealed that the two strains formed a distinct lineage within the genus Brevibacterium, most closely related to B. aurantiacum NCDO 739T (16S rRNA similarity, both 98.5%; dDDH, 46.7-46.8%; ANI, 91.9-92.1%). Strain HY170T contained MK-8(H2), diphosphatidylglycerol (DPG) and phosphatidylglycerol (PG), galactose and ribose as the predominant menaquinone, major polar lipids, and main sugars in the cell wall teichoic acids, respectively. The meso-diaminopimelic acid (meso-DAP) was the diagnostic diamino acid of the peptidoglycan found in strain HY170T. Anteiso-C15:0 and anteiso-C17:0 were the major fatty acids (> 10%) of strains HY170T and HY001, with anteiso-C17:1A predominant in strain HY170T but absent in strain HY001. Mining the genomes revealed the presence of secondary metabolite biosynthesis gene clusters encoding for non-alpha poly-amino acids (NAPAA), ectoine, siderophore, and terpene. Based on results from the phylogenetic, chemotaxonomic and phenotypic analyses, the two strains could be classified as a novel species of the genus Brevibacterium, for which the name Brevibacterium zhoupengii sp. nov. is proposed (type strain HY170T = CGMCC 1.18600T = JCM 34230T).


Assuntos
Actinobacteria , Brevibacterium , Quirópteros , Actinobacteria/genética , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Cardiolipinas/análise , China , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácidos Graxos/análise , Fezes/química , Galactose , Genômica , Peptidoglicano/química , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Ribose , Análise de Sequência de DNA , Ovinos , Sideróforos , Cloreto de Sódio/análise , Ácidos Teicoicos , Vitamina K 2/análise
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