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Journal of Bacteriology Feb 1984Major peptidoglycan transglycosylase activities, which synthesize uncross-linked peptidoglycan from lipid-linked precursors, were solubilized from the membranes of... (Comparative Study)
Comparative Study
Major peptidoglycan transglycosylase activities, which synthesize uncross-linked peptidoglycan from lipid-linked precursors, were solubilized from the membranes of Staphylococcus aureus and Micrococcus luteus and were partially purified. The transglycosylase activities were separated from penicillin-binding proteins by solubilization and by purification steps. Therefore, we concluded that these activities were not activities of the penicillin-binding proteins, which are the presumptive peptidoglycan transpeptidases in these gram-positive cocci. Unlike Escherichia coli, in which the network structure of peptidoglycan is synthesized by multiple two-headed penicillin-binding proteins with both transpeptidase and transglycosylase activities, these gram-positive cocci have cell wall peptidoglycan which seems to be synthesized by penicillin-binding protein transpeptidases and a separate transglycosylase.
Topics: Bacterial Proteins; Carboxypeptidases; Carrier Proteins; Chromatography, Affinity; Chromatography, DEAE-Cellulose; Hexosyltransferases; Kinetics; Micrococcus; Molecular Weight; Muramoylpentapeptide Carboxypeptidase; Penicillin-Binding Proteins; Peptidoglycan Glycosyltransferase; Peptidyl Transferases; Staphylococcus aureus
PubMed: 6693351
DOI: 10.1128/jb.157.2.538-544.1984 -
ACS Applied Materials & Interfaces Aug 2022Protective equipment for detecting bacterial contamination has been in high demand with increasing interest in public health and hygiene. Herein, a fiber-based visually...
Protective equipment for detecting bacterial contamination has been in high demand with increasing interest in public health and hygiene. Herein, a fiber-based visually indicating bacteria sensor (VIBS) embedded with iodonitrotetrazolium chloride is developed for the general purpose of detecting live bacteria, and its chromogenic effectiveness is investigated for Gram-negative and Gram-positive . The developed color intensity is measured by the light absorption coefficient to the scattering coefficient (/) based on the Kubelka-Munk equation, and the colorimetric sensitivities of different membranes are examined by calculating the limit of detection (LOD) and the limit of quantification (LOQ). The results demonstrate that the interactions between VIBS and bacteria depend on the wetting properties of membranes. A hydrophobic membrane shows excessive interactions at high concentrations of Gram-negative bacteria, whose cell membrane is lipophilic. The membrane blended with hydrophobic and hydrophilic polymers displays linear colorimetric responses for both Gram-negative and Gram-positive bacteria strains, demonstrating a reliable sensing capability in the range of the tested bacteria concentration. This study is significant in that explorative experimentations are performed to conceive a proof of concept of a fiber-based bacteria sensor, which is readily applicable in various fields where bacteria pose a threat.
Topics: Bacteria; Colorimetry; Escherichia coli; Gram-Negative Bacteria; Gram-Positive Bacteria; Micrococcus luteus
PubMed: 35946791
DOI: 10.1021/acsami.2c08613 -
Case Reports in Cardiology 2019Gram-positive cocci species, notably , , and account for 80 to 90% of infective endocarditis cases. HACEK microorganisms ( spp., , , , and ) account for approximately...
Gram-positive cocci species, notably , , and account for 80 to 90% of infective endocarditis cases. HACEK microorganisms ( spp., , , , and ) account for approximately 3% of cases and species account for 1-2% of cases. is a rare cause of endocarditis. To our knowledge, only 17 cases of prosthetic valve endocarditis have been described due to and a single case of native aortic valve endocarditis has been described. The following case is the only documented case of native mitral valve endocarditis. A review of the literature pertaining to Micrococcus endocarditis was performed to further characterize the entity.
PubMed: 31885931
DOI: 10.1155/2019/5907319 -
Microbial Biotechnology May 2015Biphenyl (BP)-degrading bacteria were identified to degrade various polychlorinated BP (PCB) congers in long-term PCB-contaminated sites. Exploring BP-degrading...
Culture-dependent and culture-independent characterization of potentially functional biphenyl-degrading bacterial community in response to extracellular organic matter from Micrococcus luteus.
Biphenyl (BP)-degrading bacteria were identified to degrade various polychlorinated BP (PCB) congers in long-term PCB-contaminated sites. Exploring BP-degrading capability of potentially useful bacteria was performed for enhancing PCB bioremediation. In the present study, the bacterial composition of the PCB-contaminated sediment sample was first investigated. Then extracellular organic matter (EOM) from Micrococcus luteus was used to enhance BP biodegradation. The effect of the EOM on the composition of bacterial community was investigated by combining with culture-dependent and culture-independent methods. The obtained results indicate that Proteobacteria and Actinobacteria were predominant community in the PCB-contaminated sediment. EOM from M. luteus could stimulate the activity of some potentially difficult-to-culture BP degraders, which contribute to significant enhancement of BP biodegradation. The potentially difficult-to-culture bacteria in response to EOM addition were mainly Rhodococcus and Pseudomonas belonging to Gammaproteobacteria and Actinobacteria respectively. This study provides new insights into exploration of functional difficult-to-culture bacteria with EOM addition and points out broader BP/PCB degrading, which could be employed for enhancing PCB-bioremediation processes.
Topics: Bacteria; Biotransformation; Cluster Analysis; DNA, Bacterial; DNA, Ribosomal; Environmental Microbiology; Microbial Consortia; Micrococcus luteus; Molecular Sequence Data; Organic Chemicals; Phylogeny; Polychlorinated Biphenyls; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 25675850
DOI: 10.1111/1751-7915.12266 -
Oman Journal of Ophthalmology 2019We hereby report a case of infectious keratitis after laser keratomileusis (LASIK) caused by , a commensal, managed successfully in a nonimmunocompromised individual. A...
We hereby report a case of infectious keratitis after laser keratomileusis (LASIK) caused by , a commensal, managed successfully in a nonimmunocompromised individual. A 25-year-old healthy male underwent uneventful bilateral simultaneous LASIK for myopia using disposable blades. Postoperatively, topical antibiotic and steroids were advised; he discontinued antibiotic on his own after using for a day. On the 5 postoperative day, he had pain, redness, decreased vision, and white spot in the left eye (LE) for 1-day duration. Uncorrected visual acuity (UCVA) of LE reduced to 20/80 from postoperative 20/20. Slit-lamp biomicroscopy revealed tiny infiltrate in the interface with reticular haze in the flap and stroma. Gram-positive cocci in pairs and tetrads were found on corneal smears that were collected after lifting the flap from infiltrate, stromal bed, and undersurface of the flap. was isolated on culture. The infiltrate resolved with scarring with intensive topical antibiotics. UCVA was 20/25. To the best of our knowledge, this is a first case report of post-LASIK infectious keratitis caused by .
PubMed: 31903000
DOI: 10.4103/ojo.OJO_54_2017 -
Molecules (Basel, Switzerland) Mar 2009The crude ethanolic extract and n-hexane, dichloromethane, ethyl acetate, n-butanol and aqueous fractions of Dodonaea viscosa were analyzed for antibacterial potential...
The crude ethanolic extract and n-hexane, dichloromethane, ethyl acetate, n-butanol and aqueous fractions of Dodonaea viscosa were analyzed for antibacterial potential against four Gram positive bacteria: Bacillus subtilis, Bacillus cereus, Micrococcus luteus, Staphylococcus aureus, and three Gram negative bacteria: Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa. Preliminary screening showed inhibition against Staphylococcus aureus, Micrococcus luteus, Escherichia coli and Pseudomonas aeruginosa. The thin layer chromatograms of the fractions were then subjected to contact bioautography, which showed inhibition zone at different R(f) values against Bacillus subtilis, Micrococcus luteus, Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa, indicating the presence of antibacterial components. The MIC of each fraction was determined through a 96-well micro-titer plate method. The non-viability of the organisms was ascertained by determining the MBC of the fractions.
Topics: Anti-Bacterial Agents; Gram-Negative Bacteria; Gram-Positive Bacteria; Microbial Sensitivity Tests; Plant Extracts; Sapindaceae; Solvents
PubMed: 19325527
DOI: 10.3390/molecules14031332 -
BMC Research Notes Jun 2024The purpose of this study was to evaluate antibacterial activity of pigment extracted from bacteria, isolated from soil samples. During the study, 20 soil samples were...
The purpose of this study was to evaluate antibacterial activity of pigment extracted from bacteria, isolated from soil samples. During the study, 20 soil samples were collected from different areas (forest, agriculture fields, river sides and dumping sites) of Kathmandu and Lalitpur districts which were processed for isolation of pigment producing bacteria by spread plate technique. The pigmented bacterial isolates were identified and enriched in nutrient broth. Then, pigment was extracted in 95% methanol as solvent, which was further characterized using UV-Vis Spectrophotometric and TLC analysis. The obtained crude pigment extract was processed to carry out the antimicrobial susceptibility assay using agar well diffusion method. Out of 13 total pigmented bacteria isolates, four different colored pigmented bacterial isolates (S4O, S11Y, S14P and S17G) which produced efficient pigment on nutrient agar were chosen and they were further processed. Among these isolates, S4O was identified as Staphylococcus aureus, S11Y was identified as Micrococcus luteus, S14P was identified as Micrococcus roseus and S17G was identified as Pseudomonas aeruginosa respectively. On characterization using UV-Vis Spectrophotometric and TLC analysis, the pigment extracted from isolates S4O, S11Y and S14P were found to be Carotenoids and from isolate S17G was found to be Pyocyanin in nature. The maximum antibacterial activity was shown against Staphylococcus aureus from all the four pigments extracts. The green color pigment extract from isolate S17G was found to be most effective against all the Gram-positive and Gram-negative test bacteria. This study suggests that these pigment extracts from pigmented bacteria may have beneficial antibacterial roles that can be exploited in controlling unwanted bacterial growth.
Topics: Anti-Bacterial Agents; Soil Microbiology; Pigments, Biological; Microbial Sensitivity Tests; Staphylococcus aureus; Pseudomonas aeruginosa; Bacteria; Micrococcus luteus
PubMed: 38898523
DOI: 10.1186/s13104-024-06834-4 -
Molecules (Basel, Switzerland) Dec 2017Three new prenylated furoquinoline alkaloids named lecomtequinoline A (), B (), and C (), together with the known compounds anhydroevoxine (), evoxine (), dictamnine (),...
Three new prenylated furoquinoline alkaloids named lecomtequinoline A (), B (), and C (), together with the known compounds anhydroevoxine (), evoxine (), dictamnine (), methylflindersine (), evoxanthine (), hesperidin, lupeol, -sitosterol, stigmasterol, -sitosterol-3---d-glucopyranoside, stearic acid, and myristyl alcohol, were isolated by bioassay-guided fractionation of the methanolic extracts of leaves and stem of . The structures of compounds were determined by spectroscopic methods (NMR, MS, UV, and IR) and by comparison with previously reported data. Crude extracts of leaves and stem displayed high antimicrobial activity, with Minimum Inhibitory Concentration (MIC) (values of 10.1-16.5 and 10.2-20.5 µg/mL, respectively, against , , , , and , while compounds - showed values ranging from 11.1 to 18.7 µg/mL or were inactive, suggesting synergistic effect. The extracts may find application in crude drug preparations in Western Africa where is endemic, subject to negative toxicity results in vivo
Topics: Alkaloids; Anti-Bacterial Agents; Bacillus subtilis; Escherichia coli; Humans; Microbial Sensitivity Tests; Micrococcus luteus; Molecular Structure; Plant Extracts; Plant Leaves; Plant Stems; Quinolines; Rutaceae; Staphylococcaceae
PubMed: 29267257
DOI: 10.3390/molecules23010013 -
Nucleic Acids Research Apr 1978Uracil-DNA-glycosidase that releases free uracil from single-stranded or double-stranded deaminated DNA and poly d(A-U) has been partially purified from Micrococcus...
Uracil-DNA-glycosidase that releases free uracil from single-stranded or double-stranded deaminated DNA and poly d(A-U) has been partially purified from Micrococcus luteus. The enzyme has a molecular weight of about 16,000 and can be separated from uracil-endonuclease and endonucleases (AP-endonucleases) specific for apurinic and apyrimidinic sites. Uracil-DNA-glycosidase does not act on guanine residues opposite uracil in double-stranded DNA and on xanthine in deaminated DNA. The glycosidase generates apyrimidinic sites which can serve as substrate sites for different AP-endonucleases from M. luteus.
Topics: Apurinic Acid; Binding Sites; DNA Repair; DNA, Bacterial; Deoxyribonucleases; Deoxyuracil Nucleotides; Endonucleases; Micrococcus; N-Glycosyl Hydrolases; Polydeoxyribonucleotides
PubMed: 652527
DOI: 10.1093/nar/5.4.1413 -
Microbiology (Reading, England) Aug 2002A plasmid designated pMEC2 which confers resistance to erythromycin, other macrolides, and lincomycin was detected in Micrococcus luteus strain MAW843 isolated from...
A plasmid designated pMEC2 which confers resistance to erythromycin, other macrolides, and lincomycin was detected in Micrococcus luteus strain MAW843 isolated from human skin. Curing of this approximately 4.2 kb plasmid from the host organism resulted in erythromycin sensitivity of the strain. Introduction of pMEC2 into a different M. luteus strain conferred erythromycin resistance upon this strain. Macrolide resistance in M. luteus MAW843 was an inducible trait. Induction occurred at subinhibitory erythromycin concentrations of about 0.02-0.05 micro g ml(-1). Erythromycin and oleandomycin were inducers, while spiramycin and tylosin exerted no significant inducer properties. With heterologous expression experiments in Corynebacterium glutamicum, using hybrid plasmid constructs and deletion derivatives thereof, it was possible to narrow down the location of the plasmid-borne erythromycin-resistance determinant to a region of about 1.8 kb of pMEC2. Sequence analysis of the genetic determinant, designated erm(36), identified an ORF putatively encoding a 281-residue protein with similarity to 23S rRNA adenine N(6)-methyltransferases. erm(36) was most related (about 52-54% identity) to erythromycin-resistance proteins found in high-G+C Gram-positive bacteria, including the (opportunistic) pathogenic corynebacteria Corynebacterium jeikeium, C. striatum, C. diphtheriae and Propionibacterium acnes. This is believed to be the first report of a plasmid-borne, inducible antibiotic resistance in micrococci. The possible role of non-pathogenic, saprophytic micrococci bearing antibiotic-resistance genes in the spreading of these determinants is discussed.
Topics: Anti-Bacterial Agents; DNA, Bacterial; Drug Resistance, Bacterial; Erythromycin; Gene Expression Regulation, Bacterial; Genes, Bacterial; Microbial Sensitivity Tests; Micrococcus luteus; Molecular Sequence Data; Plasmids; Sequence Analysis, DNA
PubMed: 12177341
DOI: 10.1099/00221287-148-8-2479