Abstract:
:In order to assess the roles of specific amino acid residues in the delta 5-3-ketosteroid isomerase from Pseudomonas putida biotype B during catalysis, we replaced aspartic acid 40 with asparagine (D40N) and tyrosine 16 with phenylalanine (Y16F) in the enzyme by site-directed mutagenesis. Both purified mutant enzymes resulted in profound decreases in catalytic activities, 10(3.3)-fold in the Y16F mutant and 10(6.2)-fold in the D40N mutant. Aspartic acid 40 and tyrosine 16 of the enzyme are the corresponding amino acids in the active site of the homologous enzyme from Comamonas testosteroni. Our results indicate that active-site residues of the two homologous enzymes are similar. This is opposite to the previous identification of a cysteine in an active site-directed photoinactivation study of the enzyme.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Kim SW,Choi KYdoi
10.1128/jb.177.9.2602-2605.1995subject
Has Abstractpub_date
1995-05-01 00:00:00pages
2602-5issue
9eissn
0021-9193issn
1098-5530journal_volume
177pub_type
杂志文章abstract::The CheA kinase is a central protein in the signal transduction network that controls chemotaxis in Escherichia coli. CheA receives information from a transmembrane receptor (e.g., Tar) and CheW proteins and relays it to the CheB and CheY proteins. The biochemical activities of CheA proteins truncated at various dista...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.7.2097-2101.1993
更新日期:1993-04-01 00:00:00
abstract::Pseudomonas aeruginosa is usually resistant to a wide variety of antibacterial agents, and it has been inferred, on the basis of indirect evidence, that this was due to the low permeability of its outer membrane. We determined the permeability of P. aeruginosa outer membrane directly, by measuring the rates of hydroly...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:
更新日期:1982-11-01 00:00:00
abstract::Iron-sulfur flavoproteins (ISF) constitute a widespread family of redox-active proteins in anaerobic prokaryotes. Based on sequence homologies, their overall structure is expected to be similar to that of flavodoxins, but in addition to a flavin mononucleotide cofactor they also contain a cubane-type [4Fe:4S] cluster....
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.187.11.3848-3854.2005
更新日期:2005-06-01 00:00:00
abstract::Aerobic microorganisms have evolved different strategies to withstand environmental oxidative stresses generated by various reactive oxygen species (ROS). For the facultative anaerobic human oral pathogen Streptococcus mutans, the mechanisms used to protect against ROS are not fully understood, since it does not posse...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00184-09
更新日期:2009-07-01 00:00:00
abstract::A phospholipase hydrolyzing cardiolipin to phosphatidic acid and phosphatidyl glycerol was characterized in gram-negative bacteria but was absent in preparations of gram-positive bacteria, Saccharomyces cerevisiae, and rat liver mitochondria. In cell-free extracts of Escherichia coli, Salmonella typhimurium, Proteus v...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.124.3.1148-1152.1975
更新日期:1975-12-01 00:00:00
abstract::The energetic efficiency of microbial growth is significantly reduced in cultures growing under glucose excess compared to cultures growing under glucose limitation, but the magnitude to which different energy-dissipating processes contribute to the reduced efficiency is currently not well understood. We introduce her...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.24.7308-7317.2001
更新日期:2001-12-01 00:00:00
abstract::The DNA sequence of the central regulatory locus vir of Bordetella pertussis predicts that three gene products, BvgA, BvgB, and BvgC, are encoded. Features of the predicted primary structures of these proteins and their homology to other two-component systems suggest that BvgA is located in the cytoplasm, BvgB is loca...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.14.4288-4296.1991
更新日期:1991-07-01 00:00:00
abstract::The Bacillus anthracis endospore loses resistance properties during germination when its cortex peptidoglycan is degraded by germination-specific lytic enzymes (GSLEs). Although this event normally employs several GSLEs for complete cortex removal, the SleB protein alone can facilitate enough cortex hydrolysis to prod...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00869-10
更新日期:2011-01-01 00:00:00
abstract::Unique lipids found in Azotobacter vinelandii cysts are derived primarily from beta-hydroxybutyrate used to induce encystment. Tracer studies with beta-[14C]hydroxybutyrate showed that the biosynthesis of these compounds during encystment began at 8 to 12 h after induction and reached maximal levels after 2 days, Seve...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.147.1.91-96.1981
更新日期:1981-07-01 00:00:00
abstract::A genetic approach was used to establish the route of UMP biosynthesis in Sulfolobus acidocaldarius, a member of the hyperthermophilic division (the Crenarchaeota) of the Archaea domain. Pyrimidine auxotrophs of S. acidocaldarius DG6 were isolated by direct selection and by brute-force methods. Enzymatic assay of extr...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.5.1500-1507.1993
更新日期:1993-03-01 00:00:00
abstract::We report the draft genome sequence of Paenisporosarcina sp. strain TG-20, which is 4.12 Mb in size and consists of 4,071 protein-coding genes and 76 RNA genes. The genome sequence of Paenisporosarcina sp. TG-20 may provide useful information about molecular adaptations that enhance survival in icy subsurface environm...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01472-12
更新日期:2012-12-01 00:00:00
abstract::Mycelial mats of Ascodesmis sphaerospora were fixed and embedded for electron microscopy, and thin sections of 1-mm blocks, taken from the 1st to the 7th mm behind the hyphal tips, were cut parallel to the long axis of the hyphae. The hyphal tip region is characterized by an outer zone of electron-transparent vesicles...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.95.2.658-671.1968
更新日期:1968-02-01 00:00:00
abstract::Strain IMCC9480 is a novel member of the family Oxalobacteraceae of the Betaproteobacteria, isolated from the Arctic Ocean by dilution-to-extinction culturing. Here we present the draft genome sequence of strain IMCC9480. The genome is predicted to contain genes for xanthorhodopsin, retinoid biosynthesis, carbon monox...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.05088-11
更新日期:2011-07-01 00:00:00
abstract::CytA, a 27-kDa cytolytic crystal protein of Bacillus thuringiensis subsp. israelensis, is produced only at very low levels by recombinant Escherichia coli cells unless a 20-kDa B. thuringiensis subsp. israelensis protein is also present (K. M. McLean and H. R. Whiteley, J. Bacteriol. 169:1017-1023, 1987; L. F. Adams, ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.5.1748-1756.1991
更新日期:1991-03-01 00:00:00
abstract::Acinetobacter calcoaceticus BD413 produces an extracellular lipase, which is encoded by the lipA gene. Five lipase-deficient mutants have been generated via random insertion mutagenesis. Phenotypic characterization of these mutants revealed the presence of as many as four lipolytic enzymes in A. calcoaceticus. Biochem...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.177.11.3295-3307.1995
更新日期:1995-06-01 00:00:00
abstract::The isopropylmalate isomerase in Salmonella typhimurium is the second enzyme specific for leucine biosynthesis. It is a complex enzyme composed of two subunits which are coded for by two genes of the leucine operon, leuC and leuD. The two polypeptides have been shown to copurify through successive ammonium sulfate fra...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.148.1.210-219.1981
更新日期:1981-10-01 00:00:00
abstract::ICE6013 represents one of two families of integrative conjugative elements (ICEs) identified in the pan-genome of the human and animal pathogen Staphylococcus aureus Here we investigated the excision and conjugation functions of ICE6013 and further characterized the diversity of this element. ICE6013 excision was not ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00629-16
更新日期:2017-03-28 00:00:00
abstract:UNLABELLED:Ileal lesions of patients with Crohn's disease are colonized by adherent-invasive Escherichia coli (AIEC), which is able to adhere to and to invade intestinal epithelial cells (IEC), to replicate within macrophages, and to form biofilms on the surface of the intestinal mucosa. Previous analyses indicated the...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.02499-14
更新日期:2015-04-01 00:00:00
abstract::The glutamate permeation system in Escherichia coli K-12 consists of three genes: gltC, gltS, and gltR. The genes gltC and gltS are very closely linked, and are located between the pyrE and tna loci, in the following order: tna, gltC, gltS, pyrE; gltR is located near the metA gene. The three glt genes constitute a reg...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.97.3.1118-1128.1969
更新日期:1969-03-01 00:00:00
abstract::2-Carboxybenzaldehyde dehydrogenase from the phenanthrene-degrading bacterium Nocardioides sp. strain KP7 was purified and characterized. The purified enzyme had a molecular mass of 53 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 205 kDa by gel filtration chromatography. Thus, the homotetramer ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.20.6488-6494.1997
更新日期:1997-10-01 00:00:00
abstract::A phosphatase specific for the hydrolysis of 3-deoxy-d-manno-octulosonate (KDO)-8-phosphate was purified approximately 400-fold from crude extracts of Escherichia coli B. The hydrolysis of KDO-8-phosphate to KDO and inorganic phosphate in crude extracts of E. coli B, grown in phosphate-containing minimal medium, could...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.142.1.60-68.1980
更新日期:1980-04-01 00:00:00
abstract::Type 1 pili of Escherichia coli are the prototype of the somatic class of pili found on many strains of bacteria. As a first step in the genetic analysis of type 1 piliation, an extensive series of nonpiliated derivatives of E. coli K-12 strain AW405, was characterized to produce attached or free pili when examined in...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.130.1.495-505.1977
更新日期:1977-04-01 00:00:00
abstract::In an attempt to isolate the superoxide dismutase (SOD) gene from the anaerobic sulfate-reducing bacterium Desulfoarculus baarsii, a DNA fragment was isolated which functionally complemented an Escherichia coli mutant (sodA sodB) deficient in cytoplasmic SODs. This region carries two open reading frames with sequences...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.23.6736-6742.1996
更新日期:1996-12-01 00:00:00
abstract::The gene coding for the metabolically stable 6S RNA of Escherichia coli has been cloned, sequenced, and partially characterized in expression analyses. The DNA sequence results confirm the accuracy of the previously established RNA sequence and, with genomic hybridization data, reveal that there is only one copy of th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.161.3.1162-1170.1985
更新日期:1985-03-01 00:00:00
abstract::Envelope fractions isolated from Escherichia coli K-12 C600 and from colicin-resistant and colicin-tolerant (Tol II) mutants derived from this strain were separated on sucrose gradients into cell wall-enriched and cytoplasmic membrane-enriched fractions. These fractions were tested for their ability to neutralize coli...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.108.1.422-430.1971
更新日期:1971-10-01 00:00:00
abstract::Quantitative mass conversion of intact bacterial cells of Bacillus subtilis and B. licheniformis to L-phase variants has been effected after lysozyme treatment. After subculture of the unstable L-phase variants for several months in the presence of methicillin, stable L-phase variants were obtained which grew in the a...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.116.1.456-465.1973
更新日期:1973-10-01 00:00:00
abstract::Broad-host-range plasmids and cloning vectors were conjugatively transferred to Acetobacter xylinum. One of the plasmids, RP4::Mu cts61, was used for the insertion of Tn1 into the 16-, 44-, and 64-kilobase-pair plasmids of A. xylinum. The Tn1-labeled plasmids could be mobilized by a helper plasmid. Many of the Tn1 ins...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.165.1.336-339.1986
更新日期:1986-01-01 00:00:00
abstract::The PDC1 gene coding for a pyruvate decarboxylase (PDC; EC 4.1.1.1) was deleted from the Saccharomyces cerevisiae genome. The resulting pdc1(0) mutants were able to grow on glucose and still contained 60 to 70% of the wild-type PDC activity. Two DNA fragments with sequences homologous to that of the PDC1 gene were clo...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.2.678-685.1990
更新日期:1990-02-01 00:00:00
abstract::The RimM protein in Escherichia coli is associated with free 30S ribosomal subunits but not with 70S ribosomes. A DeltarimM mutant shows a sevenfold-reduced growth rate and a reduced translational efficiency, probably as a result of aberrant assembly of the ribosomal 30S subunits. The slow growth and translational def...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.20.6095-6106.2001
更新日期:2001-10-01 00:00:00
abstract::A superfamily of transport proteins, which includes the lactose permease of Escherichia coli, contains a highly conserved motif, G-X-X-X-D/E-R/K-X-G-R/K-R/K, in the loops that connect transmembrane segments 2 and 3 and transmembrane segments 8 and 9. Previous analysis of this motif in the lactose permease (A. E. Jesse...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.8.2616-2622.1997
更新日期:1997-04-01 00:00:00