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Gene Dec 1995Menaquinone (MK) is a non-protein component of the Bacillus subtilis (Bs) electron transport chain synthesized from chorismate through a series of MK-specific reactions....
Menaquinone (MK) is a non-protein component of the Bacillus subtilis (Bs) electron transport chain synthesized from chorismate through a series of MK-specific reactions. The genes encoding biosynthesis of the naphthoquinone ring of MK are clustered at 273 degrees on the Bs chromosome. A 3.9-kb region capable of rescuing men mutants blocked in the early stages of MK biosynthesis was sequenced and found to contain three major open reading frames (ORFs). The first ORF (menF) has a predicted size of 51.8 kDa and 34% amino-acid identity with the isochorismate synthases of Escherichia coli (EntC) and Aeromonas hydrophila (AmoA), ORF2 (menD) a predicted size of 60.2 kDa and 21% identity with MenD of E. coli. ORF3 has a predicted size of 21.4 kDa and 29% identity to triacylglycerol lipase of Psychrobacter immobilis. No sequence corresponding to menC was identified. Plasmid integrational studies of the men gene cluster had suggested the presence of promoters secondary to the previously identified p1 men promoter. Sequence analysis revealed a putative promoter region upstream from ORF3.
Topics: Bacillus subtilis; Base Sequence; Carboxy-Lyases; Consensus Sequence; Gene Expression Regulation, Bacterial; Intramolecular Transferases; Isomerases; Lipase; Molecular Sequence Data; Open Reading Frames; Operon; Oxo-Acid-Lyases; RNA, Messenger; Restriction Mapping; Vitamin K
PubMed: 8566759
DOI: 10.1016/0378-1119(95)00662-1 -
The Biological Bulletin Dec 1996The antimicrobial defenses of anthozoans were investigated in vitro by extracting amoebocytes from the mesenteric filaments of the beadlet anemone, Actinia equina, and...
The antimicrobial defenses of anthozoans were investigated in vitro by extracting amoebocytes from the mesenteric filaments of the beadlet anemone, Actinia equina, and testing for their ability to phagocytose and kill the gram-negative bacterium Psychrobacter immobilis. Only the hyaline amoebocytes exhibited phagocytosis in vitro, with about 40% seen to ingest one or more bacteria over 45 min. Mixed cultures of viable amoebocytes were further found to produce O2- ions and other reactive oxygen species (ROS) after stimulation with phorbol myristate acetate or lipopolysaccharide. Co-incubation of viable amoebocytes with P. immobilis for 3 h in vitro resulted in reduced growth of the bacterium compared to saline-incubated bacteria, but because the growth of P. immobilis was also impaired by lysed control amoebocytes, the contribution made to bacterial killing by ROS could not be evaluated. Instead, as confirmed by additional experiments using lysate supernatants of the amoebocytes, it appears that the cells contain soluble bactericidal factors. The nature of these agents is at present unknown, although preliminary tests indicate that killing is not mediated by lysozyme.
PubMed: 29215925
DOI: 10.2307/1543017 -
Journal of Clinical Microbiology Sep 1992Location of the double-bond position of monounsaturated fatty acids of various bacteria was accomplished with combined gas chromatography-mass spectrometry analysis of...
Location of the double-bond position of monounsaturated fatty acids of various bacteria was accomplished with combined gas chromatography-mass spectrometry analysis of dimethyl disulfide (DMDS) derivatives. The monoenoic fatty acids from whole cells were converted to methyl esters and then to DMDS adducts and analyzed by capillary gas chromatography-mass spectrometry. The mass spectra of DMDS adducts gave an easily recognizable molecular ion and two major diagnostic ions attributable to fragmentation between the two CH3S groups located at the original site of unsaturation. Twenty-one relatively novel monoenoic fatty acids were identified among the bacteria studied. All Flavobacterium species contained i17:1 omega 8c, Bacillus alvei contained i16:1 omega 11c and i17:1 omega 12c, and Psychrobacter immobilis contained 12:1 omega 9c. Resolution of cis and trans isomers with capillary gas chromatography and subsequent mass spectrometry permitted positive identification of 16:1 omega 7c and 16:1 omega 7t in Arcobacter (Campylobacter) cryaerophila and 16:1 omega 9c and 16:1 omega 9t in Aerococcus viridans.
Topics: Bacteria; Fatty Acids, Monounsaturated; Gas Chromatography-Mass Spectrometry
PubMed: 1401029
DOI: 10.1128/jcm.30.9.2511-2512.1992 -
Journal of Bioscience and Bioengineering 2000The estA gene encoding the enzyme that catalyzes the production of (R)-beta-acetylmercaptoisobutyric acid from (R,S)-ester from Pseudomonas aeruginosa 1001, was cloned...
The estA gene encoding the enzyme that catalyzes the production of (R)-beta-acetylmercaptoisobutyric acid from (R,S)-ester from Pseudomonas aeruginosa 1001, was cloned in Escherichia coli and its nucleotide sequence was determined, revealing the presumed open reading frame encoding a polypeptide of 316 amino acid residues (948 nucleotides). The overall A + T and C + G compositions were 32.59% and 67.41%, respectively. The amino acid sequence of the estA gene product showed a significant similarity with that of the triacylglycerol lipase from Psychrobacter immobilis (38% identity), triacylglycerol lipase from Moraxella sp. (36% identity), and two forms of carboxyl esterases from Acinetobacter calcoaceticus (17% and 17% identities). The deduced amino acid sequences have a pentapeptide consensus sequence, G-X-S-X-G, having an active serine residue, and another active site, dipeptides H-G, located at 70-100 amino acids upstream of the G-X-S-X-G consensus sequence.
PubMed: 16232934
DOI: 10.1263/jbb.90.684 -
International Journal of Systematic... Jul 1994We obtained 16S ribosomal DNA (rDNA) sequence data for strains belonging to 11 species of Proteobacteria, including the type strains of Kingella kingae, Neisseria... (Comparative Study)
Comparative Study
We obtained 16S ribosomal DNA (rDNA) sequence data for strains belonging to 11 species of Proteobacteria, including the type strains of Kingella kingae, Neisseria lactamica, Neisseria meningitidis, Moraxella lacunata subsp. lacunata, [Neisseria] ovis, Moraxella catarrhalis, Moraxella osloensis, [Moraxella] phenylpyruvica, and Acinetobacter lwoffii, as well as strains of Neisseria subflava and Acinetobacter calcoaceticus. The data in a distance matrix constructed by comparing the sequences supported the proposal that the genera Acinetobacter and Moraxella and [N.] ovis should be excluded from the family Neisseriaceae. Our results are consistent with hybridization data which suggest that these excluded taxa should be part of a new family, the Moraxellaceae. The strains that we studied can be divided into the following five groups: (i) M. lacunata subsp. lacunata, [N.] ovis, and M. catarrhalis; (ii) M. osloensis; (iii) [M.] phenylpyruvica; (iv) A. calcoaceticus and A. lwoffii; and (v) N. meningitidis, N. subflava, N. lactamica, and K. kingae. We agree with the previous proposal that [N.] ovis should be renamed Moraxella ovis, as this organism is closely related to Moraxella species and not to Neisseria species. The generically misnamed taxon [M.] phenylpyruvica belongs to the proposed family Moraxellaceae, but it is sufficiently different to warrant exclusion from the genus Moraxella. Further work needs to be done to investigate genetically similar species, such as Psychrobacter immobilis, before the true generic position of this organism can be determined. Automated 16S rDNA sequencing with the PCR allows workers to accurately determine phylogenetic relationships between groups of organisms.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Acinetobacter; Base Sequence; DNA Primers; DNA, Bacterial; DNA, Ribosomal; Kingella; Molecular Sequence Data; Moraxella; Neisseria; Neisseriaceae; Phylogeny; RNA, Bacterial; RNA, Ribosomal, 16S; Sequence Homology, Nucleic Acid; Species Specificity
PubMed: 7520730
DOI: 10.1099/00207713-44-3-387 -
Comparative Biochemistry and... Jan 1995Antibacterial activity in hemocytes of the squat lobster, Galathea strigosa, the Norway lobster, Nephrops norvegicus, the common shrimp, Crangon crangon, and the giant... (Comparative Study)
Comparative Study
Antibacterial activity in hemocytes of the squat lobster, Galathea strigosa, the Norway lobster, Nephrops norvegicus, the common shrimp, Crangon crangon, and the giant Antarctic isopod, Glyptonotus antarcticus, was investigated in vitro. For all species, the marine bacterium, Psychrobacter immobilis, was used as the test organism, although with G. antarcticus, the Gram positive bacteria, Planococcus citreus and BS 68 (an isolate from Antarctic waters), were also used. Hemocyte lysate supernatants (HLS) from all four species reduced the viable count of test bacteria over a period of 4 hr showing that their hemocytes contain factors able to neutralize bacteria in vitro. However, comparison of responses produced by serially diluted samples of HLS from G. strigosa, N. norvegicus and C. crangon, revealed that activity (per unit protein) is weaker than for Carcinus maenas. Using G. antarcticus, positive activity was also observed against P. citreus and BS 68; with the response effective against all of the bacteria at both 0 degree C and 20 degrees C. These results show that: (1) the hemocytes from a range of crustacean species contain factor(s) able to neutralize bacteria in vitro; (2) antibacterial potency varies from species to species; and (3) antibacterial immunity in at least one polar invertebrate functions at low temperature.
Topics: Animals; Blood Bactericidal Activity; Crustacea; Hemocytes; Nephelometry and Turbidimetry
PubMed: 7866773
DOI: 10.1016/0300-9629(94)00157-o -
Microbios 2000A new lysis solution designated TZ, consisting of 2.0% Triton X-100 plus 2.5 mg sodium azide/ml in 0.1 M Tris-HCl buffer at pH 8.0, yielded higher levels of genomic DNA...
A new lysis solution designated TZ, consisting of 2.0% Triton X-100 plus 2.5 mg sodium azide/ml in 0.1 M Tris-HCl buffer at pH 8.0, yielded higher levels of genomic DNA from Escherichia coli O157:H7 cells compared with a number of other commonly used cell lysis methods. Ethidium bromide stained DNA bands resulting from PCR amplification of target DNA from 100 CFU of E. coli O157:H7 were readily detected following electrophoresis of agarose gels. In contrast, conventional cell lysis methods failed to detect target DNA from 100 CFU after PCR amplification. The new solution was highly effective for lysing cell suspensions of Salmonella enteritidis, Pseudomonas putida, Lysteria monocytogenes and Psychrobacter immobilis.
Topics: Buffers; DNA, Bacterial; Escherichia coli O157; Fluorometry; Image Processing, Computer-Assisted; Indicators and Reagents; Listeria monocytogenes; Polymerase Chain Reaction; Pseudomonas putida; Salmonella enteritidis; Sodium Azide
PubMed: 10756522
DOI: No ID Found