RESUMO
A primary component of all known bacterial cell walls is the peptidoglycan (PG) layer, which is composed of repeating units of sugars connected to short and unusual peptides. The various steps within PG biosynthesis are targets of potent antibiotics as proper assembly of the PG is essential for cellular growth and survival. Synthetic mimics of PG have proven to be indispensable tools to study the bacterial cell structure, growth, and remodeling. Yet, a common component of PG, meso-diaminopimelic acid (m-DAP) at the third position of the stem peptide, remains challenging to access synthetically and is not commercially available. Here, we describe the synthesis and metabolic processing of a selenium-based bioisostere of m-DAP (selenolanthionine) and show that it is installed within the PG of live bacteria by the native cell wall crosslinking machinery in mycobacterial species. This PG probe has an orthogonal release mechanism that could be important for downstream proteomics studies. Finally, we describe a bead-based assay that is compatible with high-throughput screening of cell wall enzymes. We envision that this probe will supplement the current methods available for investigating PG crosslinking in m-DAP-containing organisms.
Assuntos
Mycobacterium , Selênio , Parede Celular/química , Ácido Diaminopimélico/metabolismo , Mycobacterium/metabolismo , Peptidoglicano/químicaRESUMO
Strain EAR8T is a root endophyte isolated from Arthrocnemum macrostachyum plants collected from the Odiel marshes, Huelva (Spain). It presented in vitro plant growth-promoting properties and improved the plant growth and heavy metal accumulation in polluted soils playing an important role in phytoremediation strategies. Phenotypically, strain EAR8T cells were Gram-positive, aerobic and non-motile rods with terminal oval endospores and non-swollen sporangia which form beige, opaque, butyrous, raised and irregular colonies with undulate margins. The strain was able to grow between 15-45 °C, at pH 6.0-9.0 and tolerated 0-25â% NaCl (w/v) showing optimal growth conditions on trypticase soy agar plates supplemented with 2.5â% NaCl (w/v) at pH 7.0 and 37 °C for 24 h. Chemotaxonomic analyses showed that the isolate has meso-diaminopimelic acid as the peptidoglycan in the cell wall and MK-7 as the major respiratory quinone. The predominant fatty acids were anteiso-C15â:â0 and iso-C15â:â0 and the polar lipid profile was composed of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Phylogenetic analyses based on the whole proteomes of closest sequenced relatives confirmed that strain EAR8T is affiliated to the genus Rossellomorea and forms a clade with Rossellomorea vietnamensis 15-1T with maximum support. Genome analyses showed that EAR8T has indole-3-acetic acid and siderophore biosynthesis and transporters genes and genes related to resistance against heavy metals. Phenotypic and phylogenomic comparative studies suggested that strain EAR8T is a new representative of the genus Rossellomorea and the name Rossellomorea arthrocnemi sp. nov. is proposed. Type strain is EAR8T (=CECT 9072T=DSM 103900T).
Assuntos
Bacillaceae/classificação , Chenopodiaceae/microbiologia , Metais Pesados , Filogenia , Microbiologia do Solo , Poluentes do Solo , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Biodegradação Ambiental , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Endófitos/classificação , Endófitos/isolamento & purificação , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espanha , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
An anaerobic and aerotolerant bacterium, strain M12T, was isolated from the meibum of inflamed human meibomian glands. Cells of the strain was Gram-stain-positive, non-spore-forming and non-motile rods. Growth on trypticase soy agar plates supplemented with 5â% sheep blood was fastest at 30-37 °C under anaerobic conditions. The 16S rRNA gene sequence of the strain revealed that it belongs to the genus Cutibacterium with a 98.0â% similarity value to the closest species, Cutibacterium acnes. Genome analysis of the strain with type strains of the other Cutibacterium species resulted in digital DNA-DNA hybridization values of 32.3-22.3% and average nucleotide identity (OrthoANI) values of 86.7-73.6â%. Biochemical and physiological analyses using API rapid ID 32A and API Coryne kits revealed relatively low reactivity of the strain compared with C. acnes and Cutibacterium namnetense. The most abundant major cellular fatty acid was iso-C15â:â0. Fermentation end-products from glucose were propionate, lactate, succinate and acetate. The diagnostic diamino acid of the peptidoglycan was meso-diaminopimelic acid. Major menaquinones were MK-9(H4), MK-9(H2) and MK-9. The major peaks of the MALDI-TOF mass spectrometry spectrum were at 3493, 3712, 6986 and 7424 Da. The DNA G+C content was 59.9 mol%. Based on these findings, we propose a novel species, Cutibacterium modestum. The type strain of C. modestum is M12T (=JCM 33380T=DSM 109769T). On the basis of further genomic analysis, we also provide emended descriptions of Cutibacterium granulosum (Prévot 1938) Scholz and Kilian 2016 and Cutibacterium namnetense (Aubin et al. 2016) Nouioui et al. 2018.
Assuntos
Glândulas Tarsais/microbiologia , Filogenia , Propionibacteriaceae/classificação , Lágrimas/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Humanos , Japão , Hibridização de Ácido Nucleico , Peptidoglicano/química , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
Two novel Gram-stain-positive, irregular rod-shaped bacterial strains, dk3136T and dk3543, were isolated from the faeces of Tibetan gazelle (Procapra picticaudata) in the Qinghai-Tibet Plateau of PR China. The cells were aerobic, oxidase-negative and catalase-positive. Colonies were yellowish, circular without any observable aerial mycelium after culturing at 28 â for 3 days on brain-heart infusion (BHI) agar with 5â% sheep blood. The cells grew optimally at 28 °C, pH 7.5 and with 1â% (w/v) NaCl on BHI agar supplemented with 5â% sheep blood. Phylogenetic analysis of the 16S rRNA gene sequences revealed that their nearest phylogenetic relative was Nocardioides solisilvae Ka25T (97.9â% similarity). The results of 16S rRNA gene sequence and phylogenetic/phylogenomic analyses illustrated that N. solisilvae Ka25T, Nocardioides gilvus XZ17T, Nocardioides houyundeii 78T and Nocardioides daphniae D287T were their nearest phylogenetic neighbours. The DNA G+C contents of strains dk3136T and dk3543 were 70.3 mol% and 70.4 mol%, respectively. Their genomes exhibit lower than threshold (95-96â%) average nucleotide identity to known species of the genus Nocardioides. ll-2,6-diaminopimelic acid was the diagnostic diamino acid and MK-8(H4) was the predominant respiratory quinone. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The two strains had C18â:â1 ω9c, iso-C16â:â0 and C17â:â1 ω8c as the major fatty acids, and rhamnose and galactose as the main whole-cell sugars. On the basis of the results of our genotypic, phenotypic and biochemical analyses, we conclude that strains dk3136T and dk3543 represent a novel species in genus Nocardioides, for which the name Nocardioides jishulii sp. nov. is proposed. The type strain is dk3136T (=CGMCC 4.7570T=JCM 33496T=KCTC 49314T).
Assuntos
Actinobacteria/classificação , Antílopes/microbiologia , Fezes/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
Harmful cyanobacterial bloom (HCB) by Microcystis aeruginosa is increasingly becoming a serious concern to the environment and human health alike. Currently, many physical, chemical, and biological controls are underway to eliminate HCB, but natural chemicals are rarely used. To find a control agent with low environmental toxicity and high potential for practical use, 60 plant extracts were screened. Only Selaginella tamariscina extract killed all four Microcystis aeruginosa strains, but not the other tested bacteria. Chloroform fraction of S. tamariscina extract (CSE) showed the highest killing activity. The effects of CSE on M. aeruginosa were monitored using differential interference contrast microscopy and flow-cytometry analysis, scanning electron microscopy, and transmission electron microscopy. The images showed that CSE-treated cells were abnormally altered, with damaged cell membranes, peptidoglycan layers, and cytoplasm. Quadrupole time-of-flight liquid chromatography-mass spectrometry was used to identify amentoflavone as a major active compound. Pure amentoflavone, even at low concentrations showed a powerful killing effect on M. aeruginosa, but not on other non-cyanobacteria. Overall, in this study, we have highlighted the potentials of S. tamariscina extracts and amentoflavone as selective HCB control agents.
Assuntos
Antibacterianos/farmacologia , Biflavonoides/farmacologia , Cianobactérias/efeitos dos fármacos , Selaginellaceae/química , Membrana Celular/efeitos dos fármacos , Clorofórmio , Cianobactérias/crescimento & desenvolvimento , Citoplasma/efeitos dos fármacos , Proliferação Nociva de Algas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microcystis/efeitos dos fármacos , Microcystis/crescimento & desenvolvimento , Peptidoglicano/química , Extratos Vegetais/farmacologia , SolventesRESUMO
Two long-rod-shaped, Gram-stain-positive, obligately anaerobic and non-spore-forming strains, SNUG30099T and SNUG30370T, were isolated from faecal samples of healthy Korean subjects. The strains formed circular ivory-coloured colonies on Brain-heart infusion medium supplemented with 0.5% Difco yeast extract (YBHI) agar and cells were approximately 3.5-4.5×0.3-0.4 µm in size. Taxonomic analyses based on 16S rRNA gene sequences distinguished the strains from other species within the family Erysipelotrichaceae. The closest relative of strains SNUG30099T and SNUG30370T was Longibaculum muris (92.9â% and 93.6â% similarity, respectively), followed by Clostridium saccharogumia (92.3â% and 92.2â%). Phylogenetic inference also divided the strains into a unique branch that differed from other related strains that belong to the family Erysipelotrichaceae. DNA G+C contents based on the whole genome sequences of strains SNUG30099T and SNUG30370T were 29.2 and 30.2 mol%, respectively. Both novel strains possessed meso-diaminopimelic acid as the peptidoglycan, and phosphatidylethanolamine was observed as one of the major polar lipids. The major cellular fatty acid composition was different from those of other related taxa. In addition, the profile of biochemical activities advocated that the strains have distinct characteristics in comparison to other strains. Taken together, a novel genus, named Faecalibacillus gen. nov., is proposed, which includes the type species Faecalibacillus intestinalis sp. nov. for strain SNUG30099T and Faecalibacillus faecis sp. nov. for strain SNUG30370T. The type strains of these novel species are SNUG30099T (=KCTC 15631T=JCM 32256T) and SNUG30370T (=KCTC 15632T=JCM 32257T).
Assuntos
Fezes/microbiologia , Firmicutes/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Firmicutes/isolamento & purificação , Humanos , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNARESUMO
A Gram-stain-positive, aerobic, short-rod-shaped, non-spore-forming actinobacterial strain, designated M8JJ-5T, was isolated from a surface-sterilized bark of Neriumindicum Mill. collected from Guizhou, China, and investigated by a polyphasic approach to determine its taxonomic position. Strain M8JJ-5T grew optimally without NaCl at 28 °C and at pH 7.0-8.0. Substrate mycelia and aerial mycelia were not formed, and no diffusible pigments were observed on the media tested. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain M8JJ-5T was most closely related to the type strains of genus Amnibacterium, and shared highest 16S rRNA gene sequence similarity of 97.29â% to Amnibacterium kyonggiense KSL51201-037T. The DNA G+C content of strain M8JJ-5T was 68.6 mol%. The cell-wall peptidoglycan contained l-2,4-diaminobutyric acid and MK-12, MK-11 were the major menaquinones. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, an unidentified glycolipid, an unidentified phospholipid and an unidentified lipid, while the major fatty acids were iso-C16â:â0, anteiso-C15â:â0 and anteiso-C17â:â0. On the basis of phylogenetic, chemotaxonomic and phenotypic data, strain M8JJ-5T can be characterized to represent a novel species of the genus Amnibacterium, for which the name Amnibacteriumflavum sp. nov. is proposed. The type strain is M8JJ-5T (=KCTC 49089T=CGMCC 1.16390T).
Assuntos
Actinomycetales/classificação , Nerium/microbiologia , Filogenia , Casca de Planta/microbiologia , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/químicaRESUMO
Strain DXL2T, a Gram-stain-negative, rod-shaped, endospore-forming, motile, aerobic bacterium, was isolated from selenium mineral soil. DXL2T had the highest 16S rRNA gene sequence similarities with those of Paenibacillus ginsengarviGsoil 139T (96.8â%), Paenibacillushemerocallicola DLE-12T (95.5â%) and Paenibacillus hodogayensisSGT (95.4â%). The genome size of DXL2T was 7.24 Mb, containing 6243 predicted protein-coding genes, with a DNA G+C content of 60.2 mol%. DXL2T contained meso-diaminopimelic acid in the cell-wall peptidoglycan. The major cellular fatty acids were anteiso-C15â:â0, iso-C16â:â0 and iso-C15â:â0. The major quinone was menaquinone 7. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two aminophospholipids, an unidentified aminolipid, phosphatidylmethylethanolamine, an unidentified glycolipid and an unidentified phospholipid. Compared with the other strains, DXL2T had a specific phospholipid and a specific aminolipid, it hydrolyzed Tween 40 and could not assimilate potassium gluconate. On the basis of the phenotypic, chemotaxonomic and phylogenetic results, strain DXL2T represents a novel species within the genus Paenibacillus, for which the name Paenibacillusflagellatus sp. nov. is proposed. The type strain is DXL2T (=KCTC 33976T=CCTCC AB 2018054T).
Assuntos
Paenibacillus/classificação , Filogenia , Selênio , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Mineração , Hibridização de Ácido Nucleico , Paenibacillus/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
In the present study, we describe two novel Gram-stain-positive, irregular rod-shaped bacterial strains, 78T and 601, that had been isolated from the faeces of Tibetan antelopes at the Hoh Xil Nature Reserve, Qinghai-Tibet Plateau, China. The cells were aerobic, oxidase-negative and catalase-positive. When cultured on brain-heart infusion agar supplemented with 5â% sheep blood, colonies were cream in colour, circular, smooth and convex. Phylogenetic analysis based on the full-length 16S rRNA sequences revealed that type strain 78T and strain 601 belong to the genus Nocardioides, sharing the highest similarity to Nocardioides solisilvae JCM 31492T (98.3â%), Nocardioides gilvus XZ17T (97.4â%) and Nocardioides daejeonensis JCM 16922T (97.4â%). The average nucleotide identity values between the two novel strains and the three closely related type strains of the genus Nocardioides were lower than the 95-96â% threshold. The DNA G+C content of strains 78T and 601 were 71.2 and 71.3 mol% respectively. MK-8 (H4) was the predominant respiratory quinone and ll-2,6-diaminopimelic acid was the diagnostic diamino acid in its cell-wall peptidoglycan. Its polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, an unidentified phospholipid and an unidentified lipid. The main whole-cell sugars were rhamnose, xylose and galactose and the major fatty acids (>10â%) were C17â:â1ω8c, iso-C16â:â0 and C18â:â1ω9c. These data supported the affiliation of strains 78T and 601 to genus Nocardioides. Based on evidence collected from the phenotypic, genotypic and phylogenetic analyses, we propose a novel species named Nocardioideshouyundeii sp. nov. The type strain is 78T (=CGMCC 4.7461T=DSM 106424T).
Assuntos
Actinomycetales/classificação , Antílopes/microbiologia , Fezes/microbiologia , Filogenia , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ovinos , TibetRESUMO
A novel bacterial strain, designated T8T, isolated from ripened Pu'er tea, was investigated by using a polyphasic taxonomic approach. Cells stained Gram-positive and were aerobic, sporogenous and rod-shaped with flagella. Phylogenetic analysis of 16S rRNA gene sequences revealed the strain belonged to the family Bacillaceae in the class Bacilli and represented an independent taxon separated from other genera. Strain T8T shared low levels of 16S rRNA gene sequence similarity (<94â%) to members of other genera in the family Bacillaceae and was most closely related to Bacillus composti SgZ-9T (93.3â% sequence similarity). The DNA G+C content of strain T8T was 40 mol%. The major fatty acids (>10â%) of strain T8T were iso-C15â:â0 and iso-C16â:â0. The strain had a cell-wall type A1γ peptidoglycan with meso-diaminopimelic acid as the diagnostic diamino acid. MK-7 (62â%), MK-6 (31â%) and MK-8 (7â%) were detected as the isoprenoid quinones. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine and six unidentified phospholipids. On the basis of the polyphasic evidence presented, strain T8T is considered to represent a novel genus and species in the family Bacillaceae, for which we propose the name Pueribacillus theae gen. nov., sp. nov. The type strain is T8T (=CGMCC 1.15924T=KCTC 333888T).
Assuntos
Bacillaceae/classificação , Microbiologia de Alimentos , Filogenia , Chá/microbiologia , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/químicaRESUMO
A Gram-stain-positive, oxidase- and catalase-positive, endospore-forming, aerobic, non-motile and rod-shaped bacterium (THG-YT1T) was isolated from green tea. Growth occurred at 10-40 °C (optimum, 25-30 °C), at pH 6-8 (optimum, 7) and at 0-2â% NaCl (optimum, 0â%). Based on 16S rRNA gene sequences, phylogenetic analyses showed that strain THG-YT1T formed a distinct lineage with respect to closely related genera in the family Bacillaceae. Strain THG-YT1T was most closely related to the genera within the families Pullulanibacillus, Scopulibacillus, Tuberibacillus and Caenibacillu, with levels of 16S rRNA gene sequence similarity to the type species of members of these genera of less than 95.0â%. The menaquinone was MK-7. The polar lipids were phosphatidylethanolamine, two unidentified aminophospholipids, two unidentified aminolipids and two unidentified glycolipids. The major fatty acids of strain THG-YT1T were C18â:â3ω7c and anteiso-C17â:â0. The cell-wall peptidoglycan type was A1γ with meso-diaminopimelic acid as the diagnostic diamino acid plus alanine and glutamic acid. The cell-wall sugar was glucose. The DNA G+C content of strain THG-YT1T was determined to be 53.5 mol%. Based on the data presented here, strain THG-YT1T represents a novel species of a new genus of the family Bacillaceae, for which the name Camelliibacillus cellulosilyticus gen. nov., sp. nov. is proposed. The type strain is Camelliibacillus cellulosilyticus THG-YT1T(=KACC 19471T=CGMCC 1.16306T).
Assuntos
Bacillaceae/classificação , Filogenia , Chá/microbiologia , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Celulose , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
A novel aerobic, Gram-stain-positive, sporogenous, rod-shaped bacterial strain, 7578-1T, was isolated from ripened Pu'er tea. Based on 16S rRNA gene sequence similarity comparisons, strain 7578-1T was grouped into the genus Bacillus and appeared to be closely related to the type strains Bacillus shackletoniiLMG 18435T (98.4â%), Bacillus acidicolaDSM 14745T (97.6â%), Bacillus paralicheniformis KACC 18426T (97.2â%) and Bacillus ginsengihumi KCTC 13944T (96.7â%). The fatty acid profile containing the major fatty acids, iso-C15â:â0, anteiso-C15â:â0 and anteiso-C17â:â0 supported the allocation of strain 7578-1T to the genus Bacillus. The strain had a cell-wall type A1γ peptidoglycan with meso-diaminopimelic acid as the diagnostic diamino acid. The major menaquinone was MK-7 (95â%). The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, one unidentified phospholipid and one unidentified lipid. The average nucleotide identity values between strain 7578-1T and its most closely related species were 67.8-82.4â% by OrthoANIu analysis. The DNA-DNA relatedness value between strain 7578-1T and the type strains of closely related species were 17-39â%, again indicating that strain 7578-1T represented a novel species in the genus Bacillus. The DNA G+C content of strain 7578-1T was 36.0 mol%. On the basis of the presented polyphasic evidence, strain 7578-1T is considered to represent a novel species of the genus Bacillus, for which we propose the name Bacillus camelliae sp. nov. The type strain is 7578-1T (=CGMCC 1.15374T=KCTC 33845T).
Assuntos
Bacillus/classificação , Microbiologia de Alimentos , Filogenia , Chá/microbiologia , Bacillus/genética , Bacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
Modification of essential bacterial peptidoglycan (PG)-containing cell walls can lead to antibiotic resistance; for example, ß-lactam resistance by L,D-transpeptidase activities. Predatory Bdellovibrio bacteriovorus are naturally antibacterial and combat infections by traversing, modifying and finally destroying walls of Gram-negative prey bacteria, modifying their own PG as they grow inside prey. Historically, these multi-enzymatic processes on two similar PG walls have proved challenging to elucidate. Here, with a PG-labelling approach utilizing timed pulses of multiple fluorescent D-amino acids, we illuminate dynamic changes that predator and prey walls go through during the different phases of bacteria:bacteria invasion. We show formation of a reinforced circular port-hole in the prey wall, L,D-transpeptidaseBd-mediated D-amino acid modifications strengthening prey PG during Bdellovibrio invasion, and a zonal mode of predator elongation. This process is followed by unconventional, multi-point and synchronous septation of the intracellular Bdellovibrio, accommodating odd- and even-numbered progeny formation by non-binary division.
Assuntos
Diamino Aminoácidos/metabolismo , Aminoácidos/metabolismo , Bdellovibrio bacteriovorus/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Peptidoglicano/química , Peptidoglicano/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Bdellovibrio/metabolismo , Bdellovibrio bacteriovorus/citologia , Bdellovibrio bacteriovorus/enzimologia , Bdellovibrio bacteriovorus/genética , Escherichia coli/metabolismo , Genes Bacterianos/genética , Bactérias Gram-Negativas/metabolismo , Peptidil Transferases/genética , Peptidil Transferases/metabolismo , Deleção de Sequência , Fatores de TempoRESUMO
A crude-oil-degrading, Gram-stain-positive actinobacterial strain, RIPIT, was isolated from a soil sample collected from an oil-contaminated mud pit in Khangiran oil and gas field, in the north-east of Iran. RIPIT was strictly aerobic, catalase- and oxidase-positive. The strain grew with 0-12.5â% (w/v) NaCl (optimum 3-5â%), at 25-55 °C (optimum 45 °C) and at pH 6.0-9.5 (optimum pH 7.0). The results of 16S rRNA gene sequence comparative analysis indicated that RIPIT represents a member of the genus Prauserella, with high phylogenetic similarity to Prauserella coralliicola SCSIO 11529T (97.5â%), Prauserella endophytica SP28S-3T (97.5â%) and Prauserella marina MS498T (97.2â%). DNA-DNA relatedness values between the novel strain and P. coralliicola DSM 45821T, P. endophytica DSM 46655T and P. marina DSM 45268T were 28â, 19 and 23â%, respectively. The cell wall peptidoglycan of RIPIT contained meso-diaminopimelic acid as the diamino acid and the whole-cell sugars are galactose and arabinose. The polar lipids pattern contained phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol and two unknown phospholipids. Its cellular fatty acids pattern consisted of C17â:â1ω6c, iso-C16â:â0 and summed feature 3 (C16â:â1ω7c and/or iso-C15â:â0 2-OH), and the major respiratory quinone was MK-9(H4). The G+C content of the genomic DNA was 69 mol%. On the basis of polyphasic taxonomic data we propose that RIPIT represents a novel species of the genus Prauserella, for which the name Prauserella oleivorans sp. nov. is proposed. The type strain of Prauserellaoleivorans is RIPIT (=IBRC-M 10906T=LMG 28389T).
Assuntos
Actinomycetales/classificação , Campos de Petróleo e Gás/microbiologia , Petróleo/microbiologia , Filogenia , Microbiologia do Solo , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Irã (Geográfico) , Hibridização de Ácido Nucleico , Peptidoglicano/química , Poluição por Petróleo , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Poluentes do Solo , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
A Gram-stain-positive, non-spore-forming actinobacterial strain, designated CPCC 204077T, was isolated from the surface-sterilized root of a medicinal plant Huperzia serrata (Thunb.) collected from Sichuan Province, south-west China. The peptidoglycan type of strain CPCC 204077T was detected as A4α with an l-Lys-l-Ser-d-Asp interpeptide bridge. Galactose, glucose, rhamnose and ribose were the sugar compositions in the whole-cell hydrolysates. MK-8(H4) was the only menaquinone. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, one unidentified phospholipid and one unidentified glycolipid. The major fatty acid was iso-C16â:â0. The genomic DNA G+C content was 71.0 mol%. The phylogenetic tree based on 16S rRNA gene sequences showed that strain CPCC 204077T stood for a distinct lineage within the family Dermacoccaceaealongside the genera Branchiibius, Demetria and Barrientosiimonas, with the highest 16S rRNA gene sequence similarities to Branchiibius hedensis Mer 29717T (95.0â%), Calidifontibacter indicus PC IW02T (95.0â%), Barrientosiimonas humi 39T (94.9â%) and Demetria terragena HKI 0089T (94.7â%), and less than 94.7â% sequence similarities to all other species. Signature nucleotides in the 16S rRNA sequence showed that the strain contained the Dermacoccaceaefamily-specific 16S rRNA signature nucleotides and a genus-specific diagnostic nucleotide signature pattern. Combining the genotypic and phenotypic analyses, we propose that strain CPCC 204077T represents a novel species of a new genus in the family Dermacoccaceae with the name Allobranchiibius huperziae gen. nov., sp. nov. Strain CPCC 204077T (=NBRC 110719T=DSM 29531T) is the type strain of the type species.
Assuntos
Actinomycetales/classificação , Huperzia/microbiologia , Filogenia , Raízes de Plantas/microbiologia , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Peptidoglicano/química , Fosfolipídeos/química , Plantas Medicinais/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
Antibiotic-resistant strains of Staphylococcus aureus pose a major threat to human health and there is an ongoing need for new antibiotics to treat resistant infections. In a high throughput screen (HTS) of 230â¯000 small molecules designed to identify bioactive wall teichoic acid (WTA) inhibitors, we identified one hit, which was expanded through chemical synthesis into a small panel of potent compounds. We showed that these compounds target TarG, the transmembrane component of the two-component ATP-binding cassette (ABC) transporter TarGH, which exports WTA precursors to the cell surface for attachment to peptidoglycan. We purified, for the first time, a WTA transporter and have reconstituted ATPase activity in proteoliposomes. We showed that this new compound series inhibits TarH-catalyzed ATP hydrolysis even though the binding site maps to TarG near the opposite side of the membrane. These are the first ABC transporter inhibitors shown to block ATPase activity by binding to the transmembrane domain. The compounds have potential as therapeutic agents to treat S. aureus infections, and purification of the transmembrane transporter will enable further development.
Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Ácidos Teicoicos/farmacologia , Adenosina Trifosfatases/antagonistas & inibidores , Sítios de Ligação , Parede Celular/química , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Sistemas de Liberação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Modelos Biológicos , Estrutura Molecular , Peptidoglicano/química , Peptidoglicano/metabolismo , Ligação Proteica/efeitos dos fármacosRESUMO
An endophytic, short rod-shaped, non-motile and non-spore-forming actinobacterium, designated strain CPCC 204135T, was isolated from a surface-sterilized medicinal plant, Huperzia serrata (Thunb.), collected from Sichuan Province, south-west China. Strain CPCC 204135T was observed to grow at temperatures between 20 and 37 °C (optimum, 28-32 °C), at pH 6.0-9.0 (optimum, pH 7.0-8.0) and in the presence of 0-9.0â% (w/v) NaCl (optimum, 0-3â%). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CPCC 204135T belonged to the genus Naumannella, showing the highest level of 16S rRNA gene sequence similarity with Naumannella halotolerans DSM 24323T (97.2â%), the only species of the genus Naumannella in the family Propionibacteriaceaewith avalidly published name. The DNA-DNA hybridization value between strain CPCC 204135T and N. halotolerans DSM 24323T was 20.1±1.8â%, which is far below the accepted 70â% threshold for species delineation. The cell-wall hydrolysates contained ll-diaminopimelic acid, alanine, glycine and glutamic acid, with the peptidoglycan type of A3γ. Diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid, one unidentified aminolipid, one unidentified polar lipid and several kinds of glycolipids were detected in the polar lipids profile. MK-9(H4) was identified as the predominant menaquinone. The major cellular fatty acids (>10â%) were anteiso-C15â:â0 and iso-C16â:â0. The G+C content of the genomic DNA of strain CPCC 204135T was determined to be 71.8 mol%. On the basis of phylogenetic analysis, and phenotypic and chemotaxonomic characteristics, we concluded that strain CPCC 204135T represents a novel species of the genus Naumannella, for which the name Naumannella huperziae sp. nov. is proposed, with strain CPCC 204135T (=DSM 101717T=NBRC 111773T) as the type strain.
Assuntos
Huperzia/microbiologia , Filogenia , Propionibacteriaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , Plantas Medicinais/microbiologia , Propionibacteriaceae/genética , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
d-Glutamate (Glu) supplied by Glu racemases or d-amino acid transaminase is utilized for peptidoglycan biosynthesis in microorganisms. Comparative genomics has shown that some microorganisms, including Xanthomonas oryzae, perhaps have no orthologues of these genes. We performed shotgun cloning experiments with a d-Glu auxotrophic Escherichia coli mutant as the host and X. oryzae as the DNA donor. We obtained complementary genes, XOO_1319 and XOO_1320, which are annotated as a hypothetical protein and MurD (UDP-MurNAc-l-Ala-d-Glu synthetase), respectively. By detailed in vitro analysis, we revealed that XOO_1320 is an enzyme to ligate l-Glu to UDP-MurNAc-l-Ala, providing the first example of MurD utilizing l-Glu, and that XOO_1319 is a novel enzyme catalyzing epimerization of the terminal l-Glu of the product in the presence of ATP and Mg2+. We investigated the occurrence of XOO_1319 orthologues and found that it exists in some categories of microorganisms, including pathogenic ones.
Assuntos
Gammaproteobacteria/metabolismo , Ácido Glutâmico/metabolismo , Glicopeptídeos/metabolismo , Peptidoglicano/biossíntese , Racemases e Epimerases/metabolismo , Gammaproteobacteria/química , Ácido Glutâmico/química , Glicopeptídeos/química , Peptidoglicano/químicaRESUMO
The taxonomic status of a novel bacterium, designated strain CPCC 100226T, isolated from a traditional Chinese medicinal herbal plant, Eucommia ulmoides Oliver, was characterized by using a polyphasic approach. The aerobic isolate formed pale white colonies on tryptic soy agar. Cells were Gram-stain-positive, rod-shaped, motile and endospore-forming. Chemotaxonomic investigations revealed the presence of meso-diaminopimelic acid as the diagnostic diamino acid, MK-7 as the predominant menaquinone, anteiso-C15â:â0, iso-C15â:â0, iso-C16â:â0 and C16â:â0 as the major fatty acids, and the strain had a phospholipid pattern of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and unidentified aminophospholipids. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the isolate was closely related to Paenibacillus aestuarii DSM 23861T with 95.1â% similarity. The G+C content of the genomic DNA was 47.9 mol%. On the basis of the genotypic and phenotypic data, the isolate is considered to represent a novel species of the genus Paenibacillus. The name proposed for this taxon is Paenibacillus eucommiae sp. nov. with CPCC 100226T (=DSM 26048T=KCTC 33054T) as the type strain.
Assuntos
Eucommiaceae/microbiologia , Paenibacillus/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , Plantas Medicinais/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
Ginseng-cultivated soil is an excellent habitat for soil-borne bacteria to proliferate. A novel strain, DCY87T, was isolated from ginseng-cultivated soil in Gochang County, Republic of Korea, and subsequently characterized by polyphasic approach. Cells were rod shaped, non-motile, aerobic, Gram-reaction-positive, oxidase-negative and catalase-positive. 16S rRNA gene sequence analysis showed that strain DCY87T shared the highest similarity to 'Phycicoccus ochangensis' L1b-b9 (98.7 %). Closely phylogenetic relatives of strain DCY87T were identified: Phycicoccus ginsenosidimutans BXN5-13T (97.9 %), Phycicoccus soli THG-a14T (97.8 %), Phycicoccus bigeumensis MSL-03T (97.3 %), Phycicoccus cremeus V2M29T (97.3 %), Phycicoccus aerophilus 5516T-20T (97.3 %), Phycicoccus dokdonensis DS-8T (97.3 %) and Phycicoccus jejuensis KSW2-15T (97.1 %). The major polar lipids were classified as phosphatidylinositol and diphosphatidylglycerol. The major cellular fatty acids were composed of iso-C15 : 0, anteiso-C15:0, C17 : 0 and C17 : 1ω8c. The menaquinone was resolved as MK-8(H4). Strain DCY87T contained meso-diaminopimelic acid as diamino acid in the cell-wall peptidoglycan and glucose, xylose and rhamnose in the whole-cell sugar. The genomic DNA G+C content was calculated to be 72.7 mol%. DNA-DNA hybridization value between strain DCY87T and 'P. ochangensis' L1b-b9 was estimated to be 50 %. However, DNA-DNA hybridization value obtained between strain DCY87T and P. ginsenosidimutans BXN5-13T, P. soli THG-a14T and P. bigeumensis MSL-03T was well below 17 %. In general, polyphasic taxonomy demonstrated that DCY87T strain represented a novel species within the genus Phycicoccus. Accordingly, we propose the name Phycicoccus ginsengisoli sp. nov. The type strain is DCY87T (=KCTC 39635T=JCM 31016T).