Abstract:
:Elongation factor P (EF-P) facilitates the translation of certain peptide motifs, including those with multiple proline residues. EF-P must be posttranslationally modified for full functionality; in enterobacteria, this is accomplished by two enzymes, namely, EpmA and EpmB, which catalyze the β-lysylation of EF-P at a conserved lysine position. Mutations to efp or its modifying enzymes produce pleiotropic phenotypes, including decreases in virulence, swimming motility, and extracellular polysaccharide production, as well as proteomic perturbations. Here, we generated targeted deletion mutants of the efp, epmA, and epmB genes in the Gram-negative bacterium Erwinia amylovora, which causes fire blight, an economically important disease of apples and pears. As expected, the Δefp, ΔepmA, and ΔepmB mutants were all defective in virulence on apples, and all three mutants were complemented in trans with plasmids bearing wild-type copies of the corresponding genes. By analyzing spontaneous suppressor mutants, we found that mutations in the hrpA3 gene partially or completely suppressed the colony size, extracellular polysaccharide production, and virulence phenotypes in apple fruits and apple tree shoots but not the swimming motility phenotypes of the Δefp, ΔepmA, and ΔepmB mutants. The deletion of hrpA3 alone did not produce any alterations in any characteristics measured, indicating that the HrpA3 protein is not essential for any of the processes examined. The hrpA3 gene encodes a putative DEAH-box ATP-dependent RNA helicase. These results suggest that the loss of the HrpA3 protein at least partially compensates for the lack of the EF-P protein or β-lysylated EF-P.IMPORTANCE Fire blight disease has relatively few management options, with antibiotic application at bloom time being chief among them. As modification to elongation factor P (EF-P) is vital to virulence in several species, both EF-P and its modifying enzymes make attractive targets for novel antibiotics. However, it will be useful to understand how bacteria might overcome the hindrance of EF-P function so that we may be better prepared to anticipate bacterial adaptation to such antibiotics. The present study indicates that the mutation of hrpA3 could provide a partial offset for the loss of EF-P activity. In addition, little is known about EF-P functional interactions or the HrpA3 predicted RNA helicase, and our genetic approach allowed us to discern a novel gene associated with EF-P function.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Klee SM,Sinn JP,Holmes AC,Lehman BL,Krawczyk T,Peter KA,McNellis TWdoi
10.1128/JB.00722-18subject
Has Abstractpub_date
2019-05-08 00:00:00issue
11eissn
0021-9193issn
1098-5530pii
JB.00722-18journal_volume
201pub_type
杂志文章abstract::A mutant strain of Pediococcus cerevisiae (P. cerevisiae/PteGlu) was isolated which grows on low-folate (PteGlu) concentrations (200 pg/ml). The growth response of the parent and mutant strains to folinate (5-CHO-H(4)PteGlu) was the same. The transport of (14)C-PteGlu by P. cerevisiae/PteGlu was temperature-dependent ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.114.2.485-490.1973
更新日期:1973-05-01 00:00:00
abstract::The heat-stable enterotoxin (ST) produced by enterotoxigenic Escherichia coli is an extracellular peptide toxin that evokes watery diarrhea in the host. Two types of STs, STI and STII, have been found. Both STs are synthesized as precursor proteins and are then converted to the active forms with intramolecular disulfi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00853-08
更新日期:2008-12-01 00:00:00
abstract::The glucosamine-1-phosphate acetyltransferase activity but not the uridyltransferase activity of the bifunctional GlmU enzyme from Escherichia coli was lost when GlmU was stored in the absence of beta-mercaptoethanol or incubated with thiol-specific reagents. The enzyme was protected from inactivation in the presence ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.180.18.4799-4803.1998
更新日期:1998-09-01 00:00:00
abstract::The Saccharomyces cerevisiae mating hormone a-factor has been difficult to isolate reproducibly in sufficient yields by methods using ion-exchange chromatography, probably because of its pronounced hydrophobicity. In this work, a hydrophobic adsorbent (Amberlite XAD-2), in an insoluble bead from, was used to isolate l...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.151.3.1153-1161.1982
更新日期:1982-09-01 00:00:00
abstract:UNLABELLED:Neisseria meningitidis, an exclusively human pathogen and the leading cause of bacterial meningitis, must adapt to different host niches during human infection. N. meningitidis can utilize a restricted range of carbon sources, including lactate, glucose, and pyruvate, whose concentrations vary in host niches...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00659-15
更新日期:2015-12-07 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::Nocardia brasiliensis possess proteolytic activities that can be readily detected in a variety of media. In a modified formulation of a growth medium originally used for Streptomyces aureofaciens, N. brasiliensis was found to secrete proteolytic enzymes, one of which was capable of hydrolyzing casein. This enzyme was ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.157.2.627-631.1984
更新日期:1984-02-01 00:00:00
abstract::The utilization of glycerol as a carbon source for growth by Klebsiella aerogenes, strain 2103, involves separate aerobic (sn-glycerol-3-phosphate or G3P) and anaerobic (dihydroxyacetone or DHA) pathways of catabolism. Enzyme and transport activities of the aerobic pathway are elevated in cells grown under oxygenated ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.119.1.50-56.1974
更新日期:1974-07-01 00:00:00
abstract::Rhizobium japonicum 122 DES bacteroids from soybean nodules possess an active H(2)-oxidizing system that recycles all of the H(2) lost through nitrogenase-dependent H(2) evolution. The addition of 72 muM H(2) to suspensions of bacteroids increased O(2) uptake 300% and the rate of C(2)H(2) reduction 300 to 500%. The op...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.137.1.153-160.1979
更新日期:1979-01-01 00:00:00
abstract::Nisin is a cationic antimicrobial peptide that belongs to the group of lantibiotics. It is thought to form oligomeric pores in the target membrane by a mechanism that requires the transmembrane electrical potential delta psi and that involves local pertubation of the lipid bilayer structure. Here we show that nisin do...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.1.135-140.1997
更新日期:1997-01-01 00:00:00
abstract::Lockart, Royce Z., Jr. (The University of Texas, Austin) and Barbara Horn. Interaction of an interferon with L cells. J. Bacteriol. 85:996-1002. 1963.-Data were presented on the effect of time of exposure and concentration of an interferon in provoking viral inhibition in L cells. Populations of L cells which made red...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.85.5.996-1002.1963
更新日期:1963-05-01 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::Previous determination of the nucleotide sequence of the iol region of the Bacillus subtilis genome allowed us to predict the structure of the iol operon for myo-inositol catabolism, consisting of 10 iol genes (iolA to iouJ); iolG corresponds to idh, encoding myo-inositol 2-dehydrogenase (Idh). Primer extension analys...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.14.4591-4598.1997
更新日期:1997-07-01 00:00:00
abstract::Cells of Escherichia coli take up vitamin B(12) (cyano-cobalamin [CN-Cbl]) and iron chelates by use of sequential active transport processes. Transport of CN-Cbl across the outer membrane and its accumulation in the periplasm is mediated by the TonB-dependent transporter BtuB. Transport across the cytoplasmic membrane...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.3.706-717.2002
更新日期:2002-02-01 00:00:00
abstract::The activity of the ATP:GTP 3'-pyrophosphotransferase (guanosine pentaphosphate synthetase I [GPSI]) from Streptomyces antibioticus is stimulated maximally by methanol at 20% (vol/vol) in assay mixtures. Although the enzyme is not activated by ribosomes, its activity is stimulated by tRNA (uncharged or charged) and by...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.176.5.1482-1487.1994
更新日期:1994-03-01 00:00:00
abstract::Virulence in Shigella spp., as well as in strains of enteroinvasive Escherichia coli, is regulated by growth temperature. Previously, virR had been identified as the gene controlling the temperature-regulated expression of Shigella virulence. Since Shigella spp. and E. coli are also known to share greater than 90% DNA...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.5.2879-2881.1989
更新日期:1989-05-01 00:00:00
abstract::DNA helicase II, the product of the uvrD gene, has been implicated in DNA repair, replication, and recombination. Because the phenotypes of individual uvrD alleles vary significantly, we constructed deletion-insertion mutations in the uvrD gene to determine the phenotype of cells lacking DNA helicase II. Deletion muta...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.8.2569-2575.1991
更新日期:1991-04-01 00:00:00
abstract::NBU1 is an integrated Bacteroides element that can he mobilized from Bacteroides donors to Bacteroides recipients. Previous studies have shown that a plasmid carrying the internal mobilization region of NBU1 could be transferred by conjugation from Bacteroides thetaiotaomicron to Escherichia coli. In this report, we s...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.12.3601-3607.1996
更新日期:1996-06-01 00:00:00
abstract::X-ray fluorescence spectroscopy and electron microscopy of unstained specimens have been used to study the binding of chloropentaammineosmium(III) chloride to isolated walls of Bacillus subtilis. Native walls bound 0.220 mumol of the osmium probe per mg (dry weight) of walls, whereas walls which were chemically treate...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.149.3.1120-1123.1982
更新日期:1982-03-01 00:00:00
abstract::Analyses of the Staphylococcus epidermidis multiresistance plasmids pSK697 and pSK818 have revealed them to be closely related to the trimethoprim resistance plasmid pSK639, also isolated from S. epidermidis. pSK697 and pSK818 were found to contain a cointegrated copy of a second plasmid related to the S. epidermidis ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.20.6070-6073.1996
更新日期:1996-10-01 00:00:00
abstract::The fim operon of Salmonella enterica serovar Typhimurium encodes type 1 fimbriae. The expression of fim is controlled in response to environmental signals through a complex regulatory cascade involving the proteins FimW, FimY, and FimZ and a genetic locus, fimU, that encodes a rare arginine tRNA. We discovered that a...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01388-07
更新日期:2008-01-01 00:00:00
abstract::Although competence normally develops only in glucose-minimal salts media, mecA and mecB mutations permit the expression of competence and of late competence genes in complex media as well (D. Dubnau and M. Roggiani, J. Bacteriol. 172:4048-4055, 1990). The expression of late competence genes is dependent on the produc...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.7.4056-4063.1990
更新日期:1990-07-01 00:00:00
abstract::We examined in detail conditions necessary for making reproducible and for maximizing the amount of deoxyribonucleic acid obtained from a sex factor-containing cell as covalent circles. The results argue that under optimal conditions covalent circles are neither created nor lost during the isolation procedure. The cau...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.105.3.722-727.1971
更新日期:1971-03-01 00:00:00
abstract::Woody-Karrer, Pearl (Palo Alto Medical Research Foundation, Palo Alto, Calif.) and Joseph Greenberg. Resistance and cross resistance of Escherichia coli S mutants to the radiomimetic agent nitrofurazone. J. Bacteriol. 85:1208-1216. 1963.-Cross-resistance relationships are described for 73 mutants of Escherichia coli s...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.85.6.1208-1216.1963
更新日期:1963-06-01 00:00:00
abstract::Alpha granules were isolated from a blue-green alga, Nostoc muscorum, in large quantities and high purity by sucrose density gradient centrifugation. Sodium deoxycholate was used to eliminate membrane contamination. Isolated alpha granules from this species have average dimension of 31 nm in width and 65 nm in length....
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.105.1.331-338.1971
更新日期:1971-01-01 00:00:00
abstract::The valyl-transfer ribonucleic acid (tRNA) synthetase of Escherichia coli strain NP2907, previously described as having an elevated K(m) for adenosine triphosphate and reduced stability in vitro compared to the wild type, was found to be conditionally thermolabile in vivo. The rate of inactivation of this enzyme at a ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.109.1.315-325.1972
更新日期:1972-01-01 00:00:00
abstract::The Escherichia coli flaA gene product (also called cheC) plays a crucial role in switching flagellar rotational direction during chemotactic responses. Wild-type and mutant alleles have been cloned onto plasmid vectors, and the gene product has been identified as a 37,000-dalton protein. The flaA product appeared as ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.162.1.398-405.1985
更新日期:1985-04-01 00:00:00
abstract::Site-directed mutagenesis has been used to identify a number of charged residues essential for the transport activity of the PheP protein. These residues are highly conserved in the cluster of amino acid transporters. However, some other conserved residues and a number of aromatic residues have been shown not to be es...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.22.7500-7504.1993
更新日期:1993-11-01 00:00:00
abstract::The lining of the maltodextrin-specific maltoporin (LamB) channel exhibits a string of aromatic residues, the greasy slide, part of which has been shown previously by crystallography to be involved in substrate binding. To probe the functional role of the greasy slide, alanine scanning mutagenesis has been performed o...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.11.2994-2999.2002
更新日期:2002-06-01 00:00:00
abstract::Vegetative cells and cysts of Azotobacter vinelandii 12837 were prepared for electron microscopy by several methods assumed to preserve structural details destroyed by techniques previously reported in the literature. Examination of large numbers of cells and cysts by these methods revealed four structural details not...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.104.2.933-939.1970
更新日期:1970-11-01 00:00:00