Objective:To assess the antimicrobial and cytotoxic effects of Methylobacterium sp.isolated from soil sample of Doddabetta forest,Nilgiris,Western Ghats of Tamil Nadu.Methods:Isolation of Methylobacterium was performe...Objective:To assess the antimicrobial and cytotoxic effects of Methylobacterium sp.isolated from soil sample of Doddabetta forest,Nilgiris,Western Ghats of Tamil Nadu.Methods:Isolation of Methylobacterium was performed from soils by serial dilution plate technique.The strain was grown in modified nutrient gulucose agar(MNGA)medium to study the morphology and biochemical characteristics.Methylobacterium sp.was screened for its antimicrobial activity against pathogenic bacteria and fungi.The strain was subjected to 16S rRNA analysis and was identified as Methylohacterium sp.The nucleotide sequence of the 16S rRNA gene of the isolate exhibited close similarity with other Methylobacterium sp.and has been submitted to Genbank.The antibacterial substances were extracted using chloroform and ethyl acetate from MNGA medium in which ERI-135 had grown for 5 d at 30℃.Cytotoxic effect was also studied.GC-MS analysis was carried out.The antimicrobial activity was assessed using broth micro dilution technique.Results:Ethyl acetate extract showed activity against bacteria such as Bacillus subtilis,Klebsiella pneumoniae(K.pneumoniae),Pseudomonas aeruginosa,Salmonella typkimurium,Shigella flexneri,Enterobacter aerogenes,Staphylococcus aureu and Staphylococcus epidermidis(S.epidermidis)and fungi such as,Candida albicans and Trichophyton rubrum.The lowest minimum inhibitory concentrations were:250μg/mL against 5.epidermidis and 250μg/mL against K.pneumonia.The isolate had the ability to produce enzymes such as protease.The exyract showed cytotoxic effect in human adenocarcinoma cancer cell line(A549).GC-MS analysis showed the presence of isovaleric acid(3.64%),2-Methylbulanoic acid(5.03%),isobutyramide(5.05%),N,Noimethylformamide-di-t-butylacetal(9.79%),benzeneacetamide(15.56%),octyl butyl phthalate(3.59%)and diisooctyl phthalate(5.79)in the extract.Conclusions:Methylobaeterium sp.(ERI-135)showed promising antibacterial and cytotoxic activity.This is the first report in the antimicrobial and cytotoxic effect of Methylobaeterium sp.展开更多
Methylobacterium species,the representative bacteria distributed in phyllosphere region of plants,often synthesize carotenoids to resist harmful UV radiations.Methylobacterium extorquens is known to produce a caroteno...Methylobacterium species,the representative bacteria distributed in phyllosphere region of plants,often synthesize carotenoids to resist harmful UV radiations.Methylobacterium extorquens is known to produce a carotenoid pigment and recent research revealed that this carotenoid has a C_(30) backbone.However,its exact structure remains unknown.In the present study,the carotenoid produced by M.extorquens AM1 was isolated and its structure was determined as 4-[2-O-11Z-octadecenoyl-β-glucopyranosyl]-4,4′-diapolycopenedioc acid(1),a glycosylated C_(30) carotenoid.Furthermore,the genes related to the C_(30)carotenoid synthesis were investigated.Squalene,the precursor of the C_(30) carotenoid,is synthesized by the co-occurrence of META1p1815,META1p1816 and META1p1817.Further overexpression of the genes related to squalene synthesis improved the titer of carotenoid 1.By using gene deletion and gene complementation experiments,the glycosyltransferase META1p3663 and acyltransferase META1p3664 were firstly confirmed to catalyze the tailoring steps from 4,4′-diapolycopene-4,4′-dioic acid to carotenoid 1.In conclusion,the structure and biosynthetic genes of carotenoid 1 produced by M.extorquens AM1 were firstly characterized in this work,which shed lights on engineering M.extorquens AM1 for producing carotenoid 1 in high yield.展开更多
Methylobacterium radiotolerans is a ubiquitous organism found in the environment and is considered an opportunistic pathogen of low virulence in humans.Most human infections from M.radiotolerans have been reported in ...Methylobacterium radiotolerans is a ubiquitous organism found in the environment and is considered an opportunistic pathogen of low virulence in humans.Most human infections from M.radiotolerans have been reported in immunocompromised hosts and have been reported mainly as bloodstream infections related to central venous catheters.We present the first known case of M.radiotolerans as a causative agent of multiple brain abscesses in an immunocompromised host.展开更多
基金Supported by Entomology Research Institute.Loyolacollege,Chennai,Tamil Nadu,India(Grant No.ER1/2011/MB-05)
文摘Objective:To assess the antimicrobial and cytotoxic effects of Methylobacterium sp.isolated from soil sample of Doddabetta forest,Nilgiris,Western Ghats of Tamil Nadu.Methods:Isolation of Methylobacterium was performed from soils by serial dilution plate technique.The strain was grown in modified nutrient gulucose agar(MNGA)medium to study the morphology and biochemical characteristics.Methylobacterium sp.was screened for its antimicrobial activity against pathogenic bacteria and fungi.The strain was subjected to 16S rRNA analysis and was identified as Methylohacterium sp.The nucleotide sequence of the 16S rRNA gene of the isolate exhibited close similarity with other Methylobacterium sp.and has been submitted to Genbank.The antibacterial substances were extracted using chloroform and ethyl acetate from MNGA medium in which ERI-135 had grown for 5 d at 30℃.Cytotoxic effect was also studied.GC-MS analysis was carried out.The antimicrobial activity was assessed using broth micro dilution technique.Results:Ethyl acetate extract showed activity against bacteria such as Bacillus subtilis,Klebsiella pneumoniae(K.pneumoniae),Pseudomonas aeruginosa,Salmonella typkimurium,Shigella flexneri,Enterobacter aerogenes,Staphylococcus aureu and Staphylococcus epidermidis(S.epidermidis)and fungi such as,Candida albicans and Trichophyton rubrum.The lowest minimum inhibitory concentrations were:250μg/mL against 5.epidermidis and 250μg/mL against K.pneumonia.The isolate had the ability to produce enzymes such as protease.The exyract showed cytotoxic effect in human adenocarcinoma cancer cell line(A549).GC-MS analysis showed the presence of isovaleric acid(3.64%),2-Methylbulanoic acid(5.03%),isobutyramide(5.05%),N,Noimethylformamide-di-t-butylacetal(9.79%),benzeneacetamide(15.56%),octyl butyl phthalate(3.59%)and diisooctyl phthalate(5.79)in the extract.Conclusions:Methylobaeterium sp.(ERI-135)showed promising antibacterial and cytotoxic activity.This is the first report in the antimicrobial and cytotoxic effect of Methylobaeterium sp.
基金the National Key R&D Program of China(grant No.2021YFC2103500)National Natural Science Foundation of China(grant No.22078169)+1 种基金Natural Science Foundation of Shandong Province,China(ZR2021MC074,ZR2020MC008)Shandong Provincial Key Research and Development Plan(2021ZDSYS28).
文摘Methylobacterium species,the representative bacteria distributed in phyllosphere region of plants,often synthesize carotenoids to resist harmful UV radiations.Methylobacterium extorquens is known to produce a carotenoid pigment and recent research revealed that this carotenoid has a C_(30) backbone.However,its exact structure remains unknown.In the present study,the carotenoid produced by M.extorquens AM1 was isolated and its structure was determined as 4-[2-O-11Z-octadecenoyl-β-glucopyranosyl]-4,4′-diapolycopenedioc acid(1),a glycosylated C_(30) carotenoid.Furthermore,the genes related to the C_(30)carotenoid synthesis were investigated.Squalene,the precursor of the C_(30) carotenoid,is synthesized by the co-occurrence of META1p1815,META1p1816 and META1p1817.Further overexpression of the genes related to squalene synthesis improved the titer of carotenoid 1.By using gene deletion and gene complementation experiments,the glycosyltransferase META1p3663 and acyltransferase META1p3664 were firstly confirmed to catalyze the tailoring steps from 4,4′-diapolycopene-4,4′-dioic acid to carotenoid 1.In conclusion,the structure and biosynthetic genes of carotenoid 1 produced by M.extorquens AM1 were firstly characterized in this work,which shed lights on engineering M.extorquens AM1 for producing carotenoid 1 in high yield.
文摘Methylobacterium radiotolerans is a ubiquitous organism found in the environment and is considered an opportunistic pathogen of low virulence in humans.Most human infections from M.radiotolerans have been reported in immunocompromised hosts and have been reported mainly as bloodstream infections related to central venous catheters.We present the first known case of M.radiotolerans as a causative agent of multiple brain abscesses in an immunocompromised host.
