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BioMed Research International 2016Hemoglobin, which widely exists in all vertebrates and in some invertebrates, is possibly a precursor of antimicrobial peptides (AMPs). However, AMPs in the hemoglobin...
Hemoglobin, which widely exists in all vertebrates and in some invertebrates, is possibly a precursor of antimicrobial peptides (AMPs). However, AMPs in the hemoglobin of invertebrates have been rarely investigated. This study is the first to report the full-length cDNA, prokaryotic expression, and antimicrobial activity of UuHb-F-I from Urechis unicinctus. The full-length cDNA sequence of UuHb-F-I was 780 bp with an open-reading frame of 429 bp encoding 142 amino acids. MALDI-TOF-MS suggested that the recombinant protein of UuHb-F-I (rUuHb-F-I) yielded a molecular weight of 15,168.01 Da, and its N-terminal amino acid sequence was MGLTGAQIDAIK. rUuHb-F-I exhibited different antimicrobial activities against microorganisms. The lowest minimum inhibitory concentration against Micrococcus luteus was 2.78-4.63 μM. Our results may help elucidate the immune defense mechanism of U. unicinctus and may provide insights into new AMPs in drug discovery.
Topics: Amino Acid Sequence; Animals; Anti-Infective Agents; Antimicrobial Cationic Peptides; Base Sequence; Cell Survival; DNA, Complementary; Micrococcus luteus; Molecular Sequence Data; Polychaeta
PubMed: 27471730
DOI: 10.1155/2016/5683026 -
Applied and Environmental Microbiology May 1980Micrococcus luteus cells died relatively quickly when they were added to natural soil. The results were similar for soil in nature and as soil samples in the laboratory....
Micrococcus luteus cells died relatively quickly when they were added to natural soil. The results were similar for soil in nature and as soil samples in the laboratory. The cells died more quickly when nutrients were added to the soil. Those cells that survived soil residence exhibited a temporary lengthening of the time required for colonial growth and pigment formation on laboratory media. They had not gained increased survival capability, however. This was evident when they were retested in soil. Good survival of the M. luteus cells was noted when the soil was incubated at lowered temperatures. Some protection to the cells was provided by slow drying of the soil during incubation or by addition of NaCl. Microscopic examination of the soil revealed that the M. luteus cells were being physically destroyed and that two different bacteria were growing in the areas where the cells had lysed. It was suggested that bacterial predators in the soil might be associated with the death of the M. luteus cells.
PubMed: 16345565
DOI: 10.1128/aem.39.5.1031-1034.1980 -
Frontiers in Microbiology 2020amoebae feed by ingesting bacteria, then killing them in phagosomes. Ingestion and killing of different bacteria have been shown to rely on largely different molecular...
amoebae feed by ingesting bacteria, then killing them in phagosomes. Ingestion and killing of different bacteria have been shown to rely on largely different molecular mechanisms. One would thus expect that adapts its ingestion and killing machinery when encountering different bacteria. In this study, we investigated by RNA sequencing if and how amoebae respond to the presence of different bacteria by modifying their gene expression patterns. Each bacterial species analyzed induced a specific modification of the transcriptome. Bacteria such as , or induced a specific and different transcriptional response, while did not trigger a significant gene regulation. Although folate has been proposed to be one of the key molecules secreted by bacteria and recognized by hunting amoebae, it elicited a very specific and restricted transcriptional signature, distinct from that triggered by any bacteria analyzed here. Our results indicate that amoebae respond in a highly specific, almost non-overlapping manner to different species of bacteria. We additionally identify specific sets of genes that can be used as reporters of the response of to different bacteria.
PubMed: 32210949
DOI: 10.3389/fmicb.2020.00410 -
The Journal of Biological Chemistry Jan 1982A new purification procedure for polynucleotide phosphorylase from freeze-dried Micrococcus luteus cells gives approximately 20% yield of nearly homogeneous,...
A new purification procedure for polynucleotide phosphorylase from freeze-dried Micrococcus luteus cells gives approximately 20% yield of nearly homogeneous, primer-independent enzyme which is free of nucleic acid. The physicochemical properties of M. luteus polynucleotide phosphorylase are similar to those previously described for the enzyme from Escherichia coli in terms of Mr, subunit structure, and amino acid composition. The purified enzyme appears to be a trimer composed of three identical subunits (Mr 92,000), but it probably does not exist as such in the cell. Ferguson plot analyses of enzyme in cell extracts indicate that prior to purification the enzyme exists in oligomeric forms characterized by both higher charge and greater Mr. Changes in size and charge of oligomers which occur during purification are probably due to the dissociation of proteins and/or nucleic acids. Dissociation of the oligomers is achieved by dilution and electrophoresis, but reassociation does not occur after concentration. The poly(A) product of the initial polymerization stages migrates as a single band on both nondenaturing and urea-agarose gels. It is 13,000 +/- 2,000 nucleotides long, as measured by electron microscopy, and 8,000 nucleotides long by gel electrophoretic analysis. This poly(A) product remains bound to the enzyme after synthesis, yet can be easily obtained free of protein by proteinase K digestion.
Topics: Amino Acid Sequence; Amino Acids; Macromolecular Substances; Micrococcus; Microscopy, Electron; Molecular Weight; Poly A; Polyribonucleotide Nucleotidyltransferase; Spectrophotometry, Ultraviolet
PubMed: 7054161
DOI: No ID Found -
Folia Microbiologica Jul 2017Myxobacteria, a group of antimicrobial producing bacteria, have been successfully cultured and characterized from ten soil samples collected from different parts of...
Myxobacteria, a group of antimicrobial producing bacteria, have been successfully cultured and characterized from ten soil samples collected from different parts of Slovakia. A total of 79 myxobacteria belonging to four genera (Myxococcus, Corallococcus, Sorangium, and Polyangium) were isolated based on aspects of their life cycle. Twenty-five of them were purified, fermented, and screened for antimicrobial activities against 11 test microorganisms. Results indicated that crude extracts showed more significant activities against Gram-positive than against Gram-negative bacteria or fungi. Based on a higher degree and broader range of antimicrobial production, the two most potential extracts (K9-5, V3-1) were selected for HPLC fractionation against Micrococcus luteus and Staphylococcus aureus and LC/MS analysis of potential antibiotic metabolites. The analysis resulted in the identification of polyketide-peptide antibiotics, namely corallopyronin A and B (K9-5) and myxalamid B and C (V3-1), which were responsible for important Gram-positive activity in the observed strains. A sequence similarity search through BLAST revealed that these strains showed the highest sequence similarity to Corallococcus coralloides (K9-5, NCBI accession number KX256198) and Myxococcus xanthus (V3-1, NCBI accession number KX256197). Although screening of myxobacteria is laborious, due to difficulties in isolating cultures, this research represented the first report covering the isolation and cultivation of this challenging bacterial group from Slovakian soils as well as the screening of their antimicrobial activity, cultural identification, and secondary metabolite identification.
Topics: Anti-Bacterial Agents; Micrococcus luteus; Myxococcales; Phylogeny; Polyketides; Soil Microbiology; Staphylococcus aureus
PubMed: 28161814
DOI: 10.1007/s12223-017-0502-2 -
The FEBS Journal Feb 2010Glutaminase from Micrococcus luteus K-3 [Micrococcus glutaminase (Mglu); 456 amino acid residues (aa); 48 kDa] is a salt-tolerant enzyme. Our previous study determined...
Glutaminase from Micrococcus luteus K-3 [Micrococcus glutaminase (Mglu); 456 amino acid residues (aa); 48 kDa] is a salt-tolerant enzyme. Our previous study determined the structure of its major 42-kDa fragment. Here, using new crystallization conditions, we determined the structures of the intact enzyme in the presence and absence of its product L-glutamate and its activator Tris, which activates the enzyme by sixfold. With the exception of a 'lid' part (26-29 aa) and a few other short stretches, the structures were all very similar over the entire polypeptide chain. However, the presence of the ligands significantly reduced the length of the disordered regions: 41 aa in the unliganded structure (N), 21 aa for L-glutamate (G), 8 aa for Tris (T) and 6 aa for both L-glutamate and Tris (TG). L-glutamate was identified in both the G and TG structures, whereas Tris was only identified in the TG structure. Comparison of the glutamate-binding site between Mglu and salt-labile glutaminase (YbgJ) from Bacillus subtilis showed significantly smaller structural changes of the protein part in Mglu. A comparison of the substrate-binding pocket of Mglu, which is highly specific for L-glutamine, with that of Erwinia carotovora asparaginase, which has substrates other than L-glutamine, shows that Mglu has a larger substrate-binding pocket that prevents the binding of L-asparagine with proper interactions.
Topics: Binding Sites; Catalytic Domain; Crystallization; Crystallography, X-Ray; Glutamic Acid; Glutaminase; Glutamine; Micrococcus luteus; Tromethamine
PubMed: 20050917
DOI: 10.1111/j.1742-4658.2009.07523.x -
Journal of Materials Science. Materials... Nov 2020Literature lacks sufficient data regarding addition of natural antibacterial agents to glass ionomer cement (GICs). Hence, the aim of the study was to increase the...
Literature lacks sufficient data regarding addition of natural antibacterial agents to glass ionomer cement (GICs). Hence, the aim of the study was to increase the antimicrobial properties of GICs through its modification with mixture of plant extracts to be evaluated along with an 0.5% chlorohexidine-modified GIC (CHX-GIC) with regard to biological and compressive strength properties. Conventional GIC (freeze-dried version) and CHX were used. Alcoholic extract of Salvadora persica, Olea europaea, and Ficus carcia leaves were prepared using a Soxhlet extractor for 12 h. The plant extract mixture (PE) was added in three different proportions to the water used for preparation of the dental cement (Group 1:1 PE, 2:1 PE, and 1:2 PE). Specimens were then prepared and tested against the unmodified GIC (control) and the 0.5% CHX-GIC. Chemical analysis of the extract mixture was performed using Gas chromatography-mass spectrometry. Antimicrobial activity was evaluated using agar diffusion assay against Micrococcus luteus and Streptoccocus mutans. Compressive strength was evaluated according to ISO 9917-1:2007 using a Zwick testing machine at a crosshead speed of 0.5 mm/min. Antimicrobial activity against Streptoccocus mutans was significantly increased for all the extract-modified materials compared to the unmodified cement, and the highest concentration was comparable to the CHX-GIC mixture. The activity against Micrococcus luteus was also significantly increased, but only for the material with the highest extract concentration, and here the CHX-GIC group showed statistically the highest antimicrobial activity. Compressive strength results revealed that there was no statistically significant difference between the different mixtures and the control except for the highest tested concentration that showed the highest mean values. The plant extracts (PEs) enhanced the antimicrobial activity against S. mutans and also against M. luteus in the higher concentration while compressive strength was improved by addition of the PE at higher concentrations.
Topics: Anti-Infective Agents; Anti-Infective Agents, Local; Chlorhexidine; Coated Materials, Biocompatible; Compressive Strength; Dental Cements; Ficus; Glass Ionomer Cements; Materials Testing; Microbial Sensitivity Tests; Micrococcus luteus; Olea; Plant Extracts; Salvadoraceae; Streptococcus mutans
PubMed: 33247427
DOI: 10.1007/s10856-020-06455-w -
International Journal of Preventive... 2017Drugs targeting Angiotensin I-converting enzyme (ACE) have been used broadly in cancer chemotherapy. The recent past coupled with our results demonstrates the effective...
BACKGROUND
Drugs targeting Angiotensin I-converting enzyme (ACE) have been used broadly in cancer chemotherapy. The recent past coupled with our results demonstrates the effective use of ACE inhibitors (ACEi) as anticancer agents, and they are potentially relevant in deriving new inhibitors.
METHODS
Bacterial strains were isolated from cow milk collected in Coimbatore, Tamil Nadu, India and plated on nutrient agar medium. The identity of the strain was ascertained by 16s rRNA gene sequencing method and was submitted to the NCBI GenBank nucleotide database. Various substrates were screened for ACEi production by the fermentation with the isolated strain. ACEi was purified by sequential steps of ethanol precipitation, ion exchange column chromatography and gel filtration column chromatography. The apparent molecular mass was determined by SDS-PAGE. The anticancer property was analyzed by studying the cytotoxicity effects of ACEi using Breast cancer MCF-7 cell lines.
RESULTS
The isolate coded as BUCTL09 was selected and identified as Micrococcus luteus. Among the seven substrates, only beef extract fermented broth showed an inhibition of 79% and was reported as the best substrate. The peptide was purified and molecular mass was determined. The IC50 value of peptide was found to be 59.5 μg/ml. The purified peptide has demonstrated to induce apoptosis of cancer cell.
CONCLUSIONS
The results of this study revealed that Peptide has been determined as an active compound that inhibited the activity of ACE. These properties indicate the possibilities of the use of purified protein as a potent anticancer agent.
PubMed: 29114378
DOI: 10.4103/ijpvm.IJPVM_324_16 -
Scientific Reports Feb 2022The capture and safe storage of radioactive iodine (I or I) are of a compelling significance in the generation of nuclear energy and waste storage. Because of their...
The capture and safe storage of radioactive iodine (I or I) are of a compelling significance in the generation of nuclear energy and waste storage. Because of their physiochemical properties, Porous Organic Polymers (POPs) are considered to be one of the most sought classes of materials for iodine capture and storage. Herein, we report on the preparation and characterization of two triazine-based, nitrogen-rich, porous organic polymers, NRPOP-1 (SA = 519 m g) and NRPOP-2 (SA = 456 m g), by reacting 1,3,5-triazine-2,4,6-triamine or 1,4-bis-(2,4-diamino-1,3,5-triazine)-benzene with thieno[2,3-b]thiophene-2,5-dicarboxaldehyde, respectively, and their use in the capture of volatile iodine. NRPOP-1 and NRPOP-2 showed a high adsorption capacity of iodine vapor with an uptake of up to 317 wt % at 80 °C and 1 bar and adequate recyclability. The NRPOPs were also capable of removing up to 87% of iodine from 300 mg L iodine-cyclohexane solution. Furthermore, the iodine-loaded polymers, I@NRPOP-1 and I@NRPOP-2, displayed good antibacterial activity against Micrococcus luteus (ML), Escherichia coli (EC), and Pseudomonas aeruginosa (PSA). The synergic functionality of these novel polymers makes them promising materials to the environment and public health.
Topics: Adsorption; Anti-Bacterial Agents; Drug Resistance, Bacterial; Drug Storage; Escherichia coli; Iodine Radioisotopes; Micrococcus luteus; Nitrogen; Organic Chemicals; Polymers; Porosity; Triazines; Volatilization
PubMed: 35173259
DOI: 10.1038/s41598-022-06671-0 -
Applied and Environmental Microbiology Jun 2009Coaggregation is hypothesized to enhance freshwater biofilm development. To investigate this hypothesis, the ability of the coaggregating bacterium Sphingomonas...
Coaggregation is hypothesized to enhance freshwater biofilm development. To investigate this hypothesis, the ability of the coaggregating bacterium Sphingomonas natatoria to form single- and dual-species biofilms was studied and compared to that of a naturally occurring spontaneous coaggregation-deficient variant. Attachment assays using metabolically inactive cells were performed using epifluorescence and confocal laser scanning microscopy. Under static and flowing conditions, coaggregating S. natatoria 2.1gfp cells adhered to glass surfaces to form diaphanous single-species biofilms. When glass surfaces were precoated with coaggregation partner Micrococcus luteus 2.13 cells, S. natatoria 2.1gfp cells formed densely packed dual-species biofilms. The addition of 80 mM galactosamine, which reverses coaggregation, mildly reduced adhesion to glass but inhibited the interaction and attachment to glass-surface-attached M. luteus 2.13 cells. As opposed to wild-type coaggregating cells, coaggregation-deficient S. natatoria 2.1COGgfp variant cells were retarded in colonizing glass and did not interact with glass-surface-attached M. luteus 2.13 cells. To determine if coaggregation enhances biofilm growth and expansion, viable coaggregating S. natatoria 2.1gfp cells or the coaggregation-deficient variant S. natatoria 2.1COGgfp cells were coinoculated in flow cells with viable M. luteus 2.13 cells and allowed to grow together for 96 h. Coaggregating S. natatoria 2.1gfp cells outcompeted M. luteus 2.13 cells, and 96-h biofilms were composed predominantly of S. natatoria 2.1gfp cells. Conversely, when coaggregation-deficient S. natatoria 2.1COGgfp cells were coinoculated with M. luteus 2.13 cells, the 96-h biofilm contained few coaggregation-deficient S. natatoria 2.1 cells. Thus, coaggregation promotes biofilm integration by facilitating attachment to partner species and likely contributes to the expansion of coaggregating S. natatoria 2.1 populations in dual-species biofilms through competitive interactions.
Topics: Bacterial Adhesion; Biofilms; Fresh Water; Glass; Micrococcus luteus; Microscopy, Confocal; Sphingomonas; Staining and Labeling
PubMed: 19376917
DOI: 10.1128/AEM.02843-08