Abstract:
:The chromosomally mediated penicillinase present in three strains of Escherichia coli K-12 has been purified and characterized. Two of the strains carried the ampA gene and the third the wild-type allele. The purification involves release of the enzyme by spheroplast formation, dialysis, chromatography on sulfoethyl cellulose, and chromatography on hydroxylapatite. Enzyme from the two mutants appeared homogeneous in polyacrylamide gel electrophoresis. Enzyme from the wild-type strain gave two bands. Immunologically, the enzymes from all three strains were identical. Ultracentrifugation gave a homogeneous peak with a sedimentation coefficient of 3.4S. Gel filtration gave an estimated molecular weight of 29,000. The N-terminal amino acid residue was found to be alanine. Complete amino acid analysis showed a lack of cysteine. Ultraviolet spectra were recorded at three different pH values. The extinction coefficient at 280 nm is 21.0 for a 1% solution at pH 6.8. The optimal pH is 7.3. With enzyme from one of the resistant mutants, the following K(m) and turnover number values were obtained: for penicillin G, 12 mum and 2,080; for d-ampicillin, 6 mum and 83; for cephalosporin C, 217 mum and 18,400. The effect of different salts on the enzyme activity was tested. Under many conditions the enzyme was found to be unstable.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Linström EB,Boman HG,Steele BBdoi
10.1128/JB.101.1.218-231.1970subject
Has Abstractpub_date
1970-01-01 00:00:00pages
218-31issue
1eissn
0021-9193issn
1098-5530journal_volume
101pub_type
杂志文章abstract::The nucleotide messenger cyclic di-GMP (c-di-GMP) plays a central role in the regulation of motility, virulence, and biofilm formation in many pathogenic bacteria. EAL domain-containing phosphodiesterases are the major signaling proteins responsible for the degradation of c-di-GMP and maintenance of its cellular level...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00560-12
更新日期:2012-09-01 00:00:00
abstract::Nitroakridin 3582 (NA) formed complexes with native deoxyribonucleic acid (DNA) and with transfer ribonucleic acid (tRNA) species from Escherichia coli. Spectrophotometric titrations of NA with these nucleic acids produced numerical results from which nonlinear adsorption isotherms were derived. These curves indicated...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.108.3.1026-1033.1971
更新日期:1971-12-01 00:00:00
abstract::Desulfomonile tiedjei DCB-1, a sulfate-reducing bacterium, conserves energy for growth from reductive dehalogenation of 3-chlorobenzoate by an uncharacterized chemiosmotic process. Respiratory electron transport components were examined in D. tiedjei cells grown under conditions for reductive dehalogenation, pyruvate ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.1.40-46.1999
更新日期:1999-01-01 00:00:00
abstract::The gene tyrP, which codes for a component of the tyrosine-specific transport system, has been localized on the Escherichia coli K-12 chromosome at min 42. A tyrP-lac operon fusion was constructed and used to isolate mutants that have altered expression from the tyrP promoter. All putative tyrP operator mutations were...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.160.1.175-183.1984
更新日期:1984-10-01 00:00:00
abstract::Three gene libraries of Bordetella avium 197 DNA were prepared in Escherichia coli LE392 by using the cosmid vectors pCP13 and pYA2329, a derivative of pCP13 specifying spectinomycin resistance. The cosmid libraries were screened with convalescent-phase anti-B. avium turkey sera and polyclonal rabbit antisera against ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.23.7729-7742.1992
更新日期:1992-12-01 00:00:00
abstract::Double exbB tolQ mutants of Escherichia coli were completely resistant to bacteriophages T1 and phi 80, in contrast to strains with exbB or tolQ mutations, which were sensitive. Cells carrying mutations in exbB were partially tolerant to colicins B, D, and M and became fully tolerant by the introduction of tolQ mutati...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.11.6387-6390.1989
更新日期:1989-11-01 00:00:00
abstract::Choline-containing teichoic acid seems to be essential for the adsorption of bacteriophage Dp-1 to pneumococci. This conclusion is based on the following observations: In contrast to pneumococci grown in choline-containing medium, cells grown in medium containing ethanolamine or other submethylated aminoalcohols inste...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.151.3.1581-1590.1982
更新日期:1982-09-01 00:00:00
abstract::The occurrence of succinic dehydrogenase [succinic:(acceptor) oxidoreductase, EC 1.3.99.1] in membrane fractions of Micrococcus lysodeikticus was investigated. The enzyme could be purified 10-fold, by deoxycholate treatment. Butanol extraction of membranes yielded an active fraction, nonsedimentable at 130,000 x g for...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.107.1.230-238.1971
更新日期:1971-07-01 00:00:00
abstract::Here we announce the complete genome sequence of the copper-resistant bacterium Cupriavidus necator N-1, the type strain of the genus Cupriavidus. The genome consists of two chromosomes and two circular plasmids. Based on genome comparison, the chromosomes of C. necator N-1 share a high degree of similarity with the t...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.05660-11
更新日期:2011-09-01 00:00:00
abstract::The growth of strain araC(c)67, which produces the enzymes of the ara operon constitutively, is inhibited by the addition of ribitol. Isolation of strains resistant to ribitol yields mutants of either the araB or araC genes. A model to account for the inhibition by ribitol is discussed. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.102.2.593-595.1970
更新日期:1970-05-01 00:00:00
abstract::The gene coding for sorbitol dehydrogenase (SDH) of Rhodobacter sphaeroides Si4 was located 55 nucleotides upstream of the mannitol dehydrogenase gene (mtlK) within a previously unrecognized polyol operon. This operon probably consists of all the proteins necessary for transport and metabolization of various polyols. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.20.6335-6340.1997
更新日期:1997-10-01 00:00:00
abstract::Lysozyme is an important component of the innate immune system. It functions by hydrolyzing the peptidoglycan (PG) layer of bacteria. The human pathogen Listeria monocytogenes is intrinsically lysozyme resistant. The peptidoglycan N-deacetylase PgdA and O-acetyltransferase OatA are two known factors contributing to it...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00553-20
更新日期:2021-01-25 00:00:00
abstract::The Escherichia coli gene cluster encoding enzymatic activities responsible for the synthesis and activation of 2,3-dihydroxybenzoic acid in the formation of the catechol siderophore enterobactin was localized to a 4.2-kilobase chromosomal DNA fragment. Analysis of various subclones and transposon insertion mutations ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.9.4163-4170.1987
更新日期:1987-09-01 00:00:00
abstract::Listeria monocytogenes mutants with deletions in aroA, aroB, or aroE exhibited strong posttranscriptional upregulation of internalin A (InlA) and InlB synthesis, which resulted in a more-than-10-fold increase in InlA-mediated internalization by epithelial Caco-2 cells and a 4-fold increase in InlB-mediated internaliza...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.187.8.2836-2845.2005
更新日期:2005-04-01 00:00:00
abstract::Replication of the broad-host-range, IncPalpha plasmid RK2 requires two plasmid loci: trfA, the replication initiator gene, and oriV, the origin of replication. While these determinants are sufficient for replication in a wide variety of bacteria, they do not confer the stable maintenance of parental RK2 observed in i...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.21.6014-6026.2000
更新日期:2000-11-01 00:00:00
abstract::Type III secretion is used by many gram-negative bacterial pathogens to directly deliver protein toxins (effectors) into targeted host cells. In all cases, secretion of effectors is triggered by host cell contact, although the mechanism is unclear. In Pseudomonas aeruginosa, expression of all type III secretion-relate...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01553-07
更新日期:2008-04-01 00:00:00
abstract::The reproduction and morphogenesis of Rickettsiella chironomi, an unusual procaryotic parasite of midge larvae, was studied with electron microscopy. The morphogenic cycle was similar to that found in chlamydia and consisted of four major cell types: (i) medium-sized spherical initial bodies (ca. 1 micrometers in diam...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.143.2.995-1002.1980
更新日期:1980-08-01 00:00:00
abstract::Escherichia coli mutant N4316 is temperature sensitive and exhibits temperature-dependent suppression. These phenotypes are due to separate genes, as shown by reversion and mapping studies. The suppressor mutation was mapped and lies near argF. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.129.2.1141-1143.1977
更新日期:1977-02-01 00:00:00
abstract::The Escherichia coli htrD gene was originally isolated during a search for new genes required for growth at high temperature. Insertional inactivation of htrD leads to a pleiotropic phenotype characterized by temperature-sensitive growth in rich medium, H2O2 sensitivity, and sensitivity to cysteine. The htrD gene was ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.1.166-175.1993
更新日期:1993-01-01 00:00:00
abstract::We previously developed a genetic approach to study, with a single antibody, the topology of the outer membrane protein LamB, an Escherichia coli porin with specificity towards maltodextrins and a receptor for bacteriophage lambda. Our initial procedure consisted of inserting at random the same reporter epitope (the C...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.12.3447-3456.1996
更新日期:1996-06-01 00:00:00
abstract::Sixteen independent Azorhizobium sesbaniae ORS571 vector insertion (Vi) mutants defective in ammonium assimilation (Asm-) were selected; genomic DNA sequences flanking the insertion endpoints were cloned directly. Resulting recombinant plasmids were used to identify, by hybridization, corresponding wild-type DNA seque...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.170.3.1197-1204.1988
更新日期:1988-03-01 00:00:00
abstract::Escherichia coli sigma54-dependent phage shock protein operon (pspA to -E) transcription is under the control of PspF, a constitutively active activator. Sigma70-dependent transcription of pspF is under autogenous control by wild-type PspF but not by a DNA-binding mutant, PspF deltaHTH. Negative autoregulation of PspF...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.16.5232-5237.1997
更新日期:1997-08-01 00:00:00
abstract::The ops and tps genes of Myxococcus xanthus have ca. 90% DNA and amino acid sequence homology and are in the same orientation separated by a spacer region of only 1.4 kilobases. The products of the two genes were found to cross-react immunologically, and both were capable of Ca2+-dependent self-assembly on the surface...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.163.1.121-125.1985
更新日期:1985-07-01 00:00:00
abstract::The ability of deoxyribonucleic acid (DNA) isolated from a number of actinomycetes to reassociate with reference DNA from Actinoplanes philippinensis or Streptomyces venezuelae has been measured. All of the DNA preparations except for those from Nocardia erythropolis and Thermomonospora viridis contained 70 to 73 mole...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.102.1.30-35.1970
更新日期:1970-04-01 00:00:00
abstract::The magnetosomes of many magnetotactic bacteria consist of membrane-enveloped magnetite crystals, whose synthesis is favored by a low redox potential. However, the cellular redox processes governing the biomineralization of the mixed-valence iron oxide have remained unknown. Here, we show that in the alphaproteobacter...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00903-12
更新日期:2012-09-01 00:00:00
abstract::During nitrogen-limited growth, transcription of glnA, which codes for glutamine synthetase, requires sigma 54-RNA polymerase and the phosphorylated from the nitrogen regulator I (NRI; also called NtrC). In cells in which the lac promoter controlled expression of the gene coding for NRI, increasing the intracellular c...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.1.179-185.1992
更新日期:1992-01-01 00:00:00
abstract::Mitochondrial protein synthesis was studied during release from glucose repression in Saccharomyces cerevisiae cells bearing different mitochondrial genomes. The increase in the rate of the synthesis of mitochondrial translation products was analyzed during respiratory induction. Different kinetic patterns were found ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.153.3.1125-1132.1983
更新日期:1983-03-01 00:00:00
abstract::During the growth of Clostridium cellulolyticum in chemostat cultures with ammonia as the growth-limiting nutrient, as much as 30% of the original cellobiose consumed by C. cellulolyticum was converted to cellotriose, glycogen, and polysaccharides regardless of the specific growth rates. Whereas the specific consumpti...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.7.2010-2017.2000
更新日期:2000-04-01 00:00:00
abstract::Swarmer cell differentiation is a complex process involving the activity of many gene products. In this report, we characterized the genetic locus of Tn5 insertion in each of 12 mutants defective in swarmer cell elongation. The mutations fell into four categories affecting either flagellar biosynthesis or energetics, ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.177.3.823-828.1995
更新日期:1995-02-01 00:00:00
abstract:UNLABELLED:Biofilm formation is responsible for increased antibiotic tolerance in pathogenic bacteria. Cyclic di-GMP (c-di-GMP) is a widely used second-messenger signal that plays a key role in bacterial biofilm formation. c-di-GMP is synthesized by diguanylate cyclases (DGCs), a conserved class of enzymes absent in ma...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00742-15
更新日期:2015-09-28 00:00:00