Abstract:
:Products of the approximately 9.5-kb virB operon are proposed to direct the export of T-DNA/protein complexes across the Agrobacterium tumefaciens envelope en route to plant cells. The presence of conserved nucleoside triphosphate (NTP)-binding domains in VirB4 and VirB11 suggests that one or both proteins couple energy, via NTP hydrolysis, to T-complex transport. To assess the importance of VirB4 for virulence, a nonpolar virB4 null mutation was introduced into the pTiA6NC plasmid of strain A348. The 2.37-kb virB4 coding sequence was deleted precisely by oligonucleotide-directed mutagenesis in vitro. The resulting delta virB4 mutation was exchanged for the wild-type allele by two sequential recombination events with the counterselectable Bacillus subtilis sacB gene. Two derivatives, A348 delta B4.4 and A348 delta B4.5, sustained a nonpolar deletion of the wild-type virB4 allele, as judged by Southern blot hybridization and immunoblot analyses with antibodies specific for VirB4, VirB5, VirB10, and VirB11. Transcription of wild-type virB4 from the lac promoter restored virulence to the nonpolar null mutants on a variety of dicotyledonous species, establishing virB4 as an essential virulence gene. A substitution of glutamine for Lys-439 and a deletion of Gly-438, Lys-439, and Thr-440 within the glycine-rich NTP-binding domain (Gly-Pro-Iso-Gly-Arg-Gly-Lys-Thr) abolished complementation of A348 delta B4.4 or A348 delta B4.5, demonstrating that an intact NTP-binding domain is critical for VirB4 function. Merodiploids expressing both the mutant and wild-type virB4 alleles exhibited lower virulence than A348, suggesting that VirB4, a cytoplasmic membrane protein, may contribute as a homo- or heteromultimer to A. tumefaciens virulence.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Berger BR,Christie PJdoi
10.1128/jb.175.6.1723-1734.1993subject
Has Abstractpub_date
1993-03-01 00:00:00pages
1723-34issue
6eissn
0021-9193issn
1098-5530journal_volume
175pub_type
杂志文章abstract::More than 98% of reported human listeriosis cases are caused by Listeria monocytogenes serotypes within lineages I and II. Serotypes within lineage III (4a and 4c) are commonly isolated from environmental and food specimens. We report the first complete genome sequence of a lineage III isolate, HCC23, which will be us...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.05236-11
更新日期:2011-07-01 00:00:00
abstract::A cell permeabilization procedure is described that reduces viability less than 10% and does not significantly reduce the rates of ribonucleic acid and protein synthesis when appropriately supplemented. Permeabilization abolishes the normal stringent coupling of protein and ribonucleic acid synthesis. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.118.3.1186-1189.1974
更新日期:1974-06-01 00:00:00
abstract::In Enterococcus faecalis, the site 2 protease Eep generates sex pheromones, including cAM373. Intriguingly, in Staphylococcus aureus, a peptide similar to cAM373, named cAM373_SA, is produced from the camS gene. Here, we report that the staphylococcal Eep homolog is not only responsible for the production of cAM373_SA...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00046-20
更新日期:2020-07-09 00:00:00
abstract::top mutations (formerly supX) eliminate DNA topoisomerase I activity and suppress the leu-500 promoter mutation in Salmonella typhimurium (K. M. Overbye, S. K. Basu, and P. Margolin, Cold Spring Harbor Symp. Quant. Biol. 47:785-791, 1983). Sublethal doses of coumermycin which reduce intracellular levels of supercoilin...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.164.2.947-949.1985
更新日期:1985-11-01 00:00:00
abstract::Tn4551, a clindamycin resistance (Ccr) transposon from the R plasmid pBI136, was cloned onto an Escherichia coli-Bacteroides shuttle vector which could replicate normally in E. coli but was maintained unstably in Bacteroides fragilis. To aid in cloning and to ensure maintenance of Tn4551 in E. coli, a kanamycin resist...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.8.3450-3457.1987
更新日期:1987-08-01 00:00:00
abstract::Campylobacter jejuni 81-176 lipooligosaccharide (LOS) is composed of two covalently linked domains: lipid A, a hydrophobic anchor, and a nonrepeating core oligosaccharide, consisting of an inner and outer core region. We report the isolation and characterization of the deepest rough C. jejuni 81-176 mutant by insertio...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.188.9.3273-3279.2006
更新日期:2006-05-01 00:00:00
abstract::Gene amplifications have been detected as a transitory phenomenon in bacterial cultures. They are predicted to contribute to rapid adaptation by simultaneously increasing the expression of genes clustered on the chromosome. However, genome amplifications have rarely been described in natural isolates. Through DNA arra...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01357-07
更新日期:2008-01-01 00:00:00
abstract::During insect infection Photorhabdus luminescens emits light and expresses virulence factors, including insecticidal toxin complexes (Tcs) and an RTX-like metalloprotease (Prt). Using quantitative PCR and protein assays, we describe the expression patterns of these factors both in culture and during insect infection a...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.20.5834-5839.2001
更新日期:2001-10-01 00:00:00
abstract::Early log-phase cells of Mycoplasma gallisepticum A5969 were synchronized by holding in Eagle minimal essential medium (MEM) for 2 h. When transferred out of MEM into tryptose medium, the cells exhibited synchronous growth. Deoxyribonucleic acid (DNA) synthesis proceeded continuously during this growth but stopped dur...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.115.1.117-120.1973
更新日期:1973-07-01 00:00:00
abstract:UNLABELLED:Edwardsiella tarda is an important pathogenic bacterium that can replicate in macrophages. However, how the intramacrophage infection process affects the virulence of this bacterium is essentially unknown. Here, we show that E. tarda replicates and induces a caspase-1-dependent cell pyroptosis in a murine ma...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00978-15
更新日期:2016-04-28 00:00:00
abstract::Strains of avian pathogenic Escherichia coli (APEC), the common pathogen of avian colibacillosis, encounter reactive oxygen species (ROS) during the infection process. Superoxide dismutases (SODs), acting as antioxidant factors, can protect against ROS-mediated host defenses. Our previous reports showed that the sodA ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00625-18
更新日期:2019-02-25 00:00:00
abstract::Siderophore-mediated iron transport in Pseudomonas aeruginosa is dependent upon the cytoplasmic membrane-associated TonB1 energy coupling protein for activity. To assess the functional significance of the various regions of this molecule and to identify functionally important residues, the tonB1 gene was subjected to ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.6.1503-1513.2002
更新日期:2002-03-01 00:00:00
abstract::Whole cells of Bacillus subtilis transported d-alanine and l-alanine by two different systems. The high-affinity system (K(m) of 1 muM and V(max) of 0.6 to 0.8 nmol/min per mg of protein) was specific for the two stereoisomers of alanine. The low-affinity system (K(m) of 10 muM for l-alanine and 20 muM for d-alanine a...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.120.3.1085-1092.1974
更新日期:1974-12-01 00:00:00
abstract::Studies of mitochondrial biogenesis in yeast have been hampered by a lack of suitable membrane markers in anaerobically grown cells subsequently grown in air. Cytochrome c peroxidase activity and subcellular location was studied to determine whether it would be a useful marker for an analysis of mitochondrial formatio...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.94.4.1225-1235.1967
更新日期:1967-10-01 00:00:00
abstract::The bacteriophage T4 MotA protein is a transcriptional activator of T4-modified host RNA polymerase and is required for activation of the middle class of T4 promoters. MotA alone binds to the -30 region of T4 middle promoters, a region that contains the MotA box consensus sequence [(t/a)(t/a)TGCTT(t/c)A]. We report th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.21.6133-6139.1996
更新日期:1996-11-01 00:00:00
abstract::ATP sulfurylase is a key enzyme in the energy-generating sulfur oxidation pathways of many chemoautotrophic bacteria. The utilization of reduced sulfur compounds to fuel CO2 fixation by the still-uncultured bacterial endosymbionts provides the basis of nutrition in invertebrates, such as the tubeworm Riftia pachyptila...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.176.12.3723-3729.1994
更新日期:1994-06-01 00:00:00
abstract::Two deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerases (I, II) have been solubilized from isolated Saccharomyces cerevisiae nuclei. The enzymes can be separated by chromatography on O-diethylaminoethyl Sephadex. Both enzymes are active with high-molecular-weight nuclear yeast DNA, although RNA po...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.114.1.1-6.1973
更新日期:1973-04-01 00:00:00
abstract::Alcaligenes sp. strain CC1 is able to grow on several alpha-chlorinated aliphatic acids (2-chlorobutyrate, 2-chloropropionate, and chloroacetate), as well as on the beta-chlorinated four-carbon aliphatic acids trans-3-chlorocrotonate, cis-3-chlorocrotonate, and 3-chlorobutyrate as sole carbon and energy sources. Dehal...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.3.1428-1434.1989
更新日期:1989-03-01 00:00:00
abstract::Analysis of chlorobenzene-degrading transconjugants of Pseudomonas putida F1 which had acquired the genes for chlorocatechol degradation (clc) from Pseudomonas sp. strain B13 revealed that the clc gene cluster was present on a 105-kb amplifiable genetic element (named the clc element). In one such transconjugant, P. p...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.180.17.4360-4369.1998
更新日期:1998-09-01 00:00:00
abstract::The interaction between endonuclease V, the cyclobutane pyrimidine dimer-specific N-glycosylase/abasic lyase from bacteriophage T4, and DNA was investigated by DNase I footprinting methods. The catalytically inactive mutant E23Q was found to interact with a smaller region of DNA at the abasic site analog, tetrahydrofu...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.177.17.5166-5168.1995
更新日期:1995-09-01 00:00:00
abstract::Here we show that the type III secretion gatekeeper protein SepL resembles an aberrant effector protein in binding to a class 1 type III secretion chaperone (Orf12, here renamed CesL). We also show that short N-terminal fragments (≤70 amino acids) from SepL are capable of targeting fusion proteins for secretion and tr...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00760-10
更新日期:2010-11-01 00:00:00
abstract::Catabolic mannopine (MOP) cyclase encoded by certain Agrobacterium Ti and Ri plasmids lactonizes MOP to agropine (AGR). The enzyme, purified to homogeneity from a recombinant clone, has a molecular mass of 45 kDa as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and size exclusion chromatography...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.8.2427-2430.1996
更新日期:1996-04-01 00:00:00
abstract::Extracellular secretion of Serratia marcescens nuclease occurs as a two-step process via a periplasmic intermediate. Unlike other extracellular proteins secreted by gram-negative bacteria by the general secretory pathway, nuclease accumulates in the periplasm in its active form for an unusually long time before its ex...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.3.677-683.1997
更新日期:1997-02-01 00:00:00
abstract::The crystal structure of a small, basic DNA binding protein, Sso10b2, from the thermoacidophilic archaeon Sulfolobus solfataricus was determined by the Zn multiwavelength anomalous diffraction method and refined to 1.85 A resolution. The 89-amino-acid protein adopts a betaalphabetaalphabetabeta topology. The structure...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.185.14.4066-4073.2003
更新日期:2003-07-01 00:00:00
abstract::Eight metH mutants in Salmonella typhimurium with closely linked sites of mutation which could grow only on methionine were isolated from a metE mutant deficient in N(5)-methyltetrahydropteroyltriglutamate-homocysteine transmethylase; their deficiency in cobalamin-dependent N(5)-methyltetrahydrofolate-homocysteine tra...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.100.1.377-382.1969
更新日期:1969-10-01 00:00:00
abstract::SufA, IscA, and Nfu have been proposed to function as scaffolds in the assembly of Fe/S clusters in bacteria. To investigate the roles of these proteins further, single and double null-mutant strains of Synechococcus sp. strain PCC 7002 were constructed by insertional inactivation of genes homologous to sufA, iscA, an...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.188.9.3182-3191.2006
更新日期:2006-05-01 00:00:00
abstract::This article contains an analysis of a version of the well-known inhibitor-dilution model for the control of initiation of chromosome replication in bacteria. According to this model, an unstable inhibitor interacts with an initiation primer in a hit-and-destroy fashion to prevent successful initiation; both constitue...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.11.5231-5240.1987
更新日期:1987-11-01 00:00:00
abstract::The DnaK protein of Zymomonas mobilis (DnaKz) was identified and found to be 80% identical to the DnaK protein of Escherichia coli on the basis of the sequence of the N-terminal 21 amino acids. The dnaKz gene was cloned and found to be expressed in a thermosensitive dnaK mutant of Escherichia coli. Expression of the f...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.10.3228-3231.1993
更新日期:1993-05-01 00:00:00
abstract::Lectin activity in a host-mycoparasite relationship was demonstrated with Rhizoctonia solani and Trichoderma harzianum. Attachment of O but not A and B erythrocytes to hyphae occurred on R. solani but not on its mycoparasite. This phenomenon, which was Ca2+ and Mn2+ dependent, was prevented by galactose, present in T....
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.154.3.1431-1435.1983
更新日期:1983-06-01 00:00:00
abstract::Phosphate import is required for the growth of mycobacteria and is regulated by environmental inorganic phosphate (P(i)) concentrations, although the mechanism of this regulation has not been characterized. The expression of genes involved in P(i) acquisition is frequently regulated by two-component regulatory systems...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00190-07
更新日期:2007-08-01 00:00:00