Abstract:
:The Dps-like peroxide resistance protein (Dpr) is essential for H2O2 stress tolerance and aerobic growth of the oral pathogen Streptococcus mutans Dpr accumulates during oxidative stress, protecting the cell by sequestering iron ions and thereby preventing the generation of toxic hydroxyl radicals that result from the interaction of iron with H2O2 Previously, we reported that the SpxA1 and SpxA2 regulators positively regulate expression of dpr in S. mutans Using an antibody raised against S. mutans Dpr, we confirmed at the protein level the central and cooperative nature of SpxA1 and SpxA2 regulation in Dpr production. During phenotypic characterization of the S. mutans Δdpr strain, we observed the appearance of distinct colony variants, which sometimes lost the oxidative stress sensitivity typical of Δdpr strains. Whole-genome sequencing of these phenotypically distinct Δdpr isolates revealed that a putative iron transporter operon, smu995-smu998, was a genomic hot spot with multiple single nucleotide polymorphisms identified within the different isolates. Deletion of smu995 or the entire smu995-smu998 operon in the Δdpr background strain completely reversed the oxidative stress-sensitive phenotypes associated with dpr inactivation. Conversely, inactivation of genes encoding the ferrous iron transport system FeoABC did not alleviate phenotypes of the Δdpr strain. Preliminary characterization of strains lacking smu995-smu998, feoABC, and the iron/manganese transporter gene sloABC revealed the interactive nature of these three systems in iron transport but also indicated that there may be additional iron uptake systems in S. mutansIMPORTANCE The dental caries-associated pathogen Streptococcus mutans routinely encounters oxidative stress within the human plaque biofilm. Previous studies revealed that the iron-binding protein Dpr confers protection toward oxidative stress by limiting free iron availability, which is associated with the generation of toxic hydroxyl radicals. Here, we report the identification of spontaneously occurring mutations within Δdpr strains. Several of those mutations were mapped to the operon smu995-smu998, revealing a previously uncharacterized system that appears to be important in iron acquisition. Disruption of the smu995-smu998 operon resulted in reversion of the stress-sensitive phenotype typical of a Δdpr strain. Our data suggest that the Smu995-Smu998 system works along with other known metal transport systems of S. mutans, i.e., FeoABC and SloABC, to coordinate iron uptake.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Ganguly T,Kajfasz JK,Miller JH,Rabinowitz E,Galvão LCC,Rosalen PL,Abranches J,Lemos JAdoi
10.1128/JB.00062-18subject
Has Abstractpub_date
2018-06-25 00:00:00issue
14eissn
0021-9193issn
1098-5530pii
JB.00062-18journal_volume
200pub_type
杂志文章abstract::The fermentative hyperthermophile Pyrococcus furiosus contains an NADPH-utilizing, heterotetrameric (alphabetagammadelta), cytoplasmic hydrogenase (hydrogenase I) that catalyzes both H(2) production and the reduction of elemental sulfur to H(2)S. Herein is described the purification of a second enzyme of this type, hy...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.7.1864-1871.2000
更新日期:2000-04-01 00:00:00
abstract::The ability of different metal ions to promote transformation of Pseudomonas aeruginosa by deoxyribonucleic acid of the plasmid RP1 was examined. CaCl2, MgCl2, and MnCl2 were found to promote such transformation, although at different frequencies and with the optimum response at different concentrations. Only MgCl2 pr...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.140.1.37-42.1979
更新日期:1979-10-01 00:00:00
abstract::Genetic and segregation analysis of Escherichia coli strains containing a partial duplication of the trp operon reveal that the 2.5-min-long region trpD-purB is duplicated in tandem in the chromosome. The adjacent loci cysB and fabD are not duplicated. Although one copy of the duplicated region is longer than the maxi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.133.2.650-660.1978
更新日期:1978-02-01 00:00:00
abstract::The arginine biosynthetic precursors, ornithine, citrulline, and argininosuccinate, inhibit arginyl-transfer ribonucleic acid (tRNA) synthetase (EC 6.1.1.13, arginine: soluble RNA ligase, adenosine monophosphate) activity in the in vitro attachment assay system. Ornithine is the most potent, argininosuccinate is next,...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.107.2.589-591.1971
更新日期:1971-08-01 00:00:00
abstract::The metD D-methionine transporter locus of Escherichia coli was identified as the abc-yaeE-yaeC cluster (now renamed metNIQ genes). The abc open reading frame is preceded by tandem MET boxes bracketed by the -10 and -35 boxes of a promoter. The expression driven by this promoter is controlled by the MetJ repressor and...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.17.4930-4932.2002
更新日期:2002-09-01 00:00:00
abstract::Fowler, Audree V. (University of California, Los Angeles), and Irving Zabin. Effects of dimethylsulfoxide on the lactose operon in Escherichia coli. J. Bacteriol. 92:353-357. 1966.-Dimethylsulfoxide (DMSO) at a concentration of 5% (v/v) in the culture medium inhibits the growth of Escherichia coli to only a slight ext...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.92.2.353-357.1966
更新日期:1966-08-01 00:00:00
abstract::Burkholderia cepacia AC1100 metabolizes 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) via formation of 5-chlorohydroxyquinol (5-CHQ), hydroxyquinol (HQ), maleylacetate, and beta-oxoadipate. The step(s) leading to the dechlorination of 5-CHQ to HQ has remained unidentified. We demonstrate that a dechlorinating enzyme, Tf...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.180.17.4667-4675.1998
更新日期:1998-09-01 00:00:00
abstract::Vibrio cholerae, the causative agent of cholera, has a sheathed, polar flagellum, and motility has been linked to virulence. An operon with two genes, flgO and flgP (VC2207 and VC2206), is positively regulated by FlrC, the activator of class III flagellar genes. Deletion of flgP results in a nonmotile phenotype, demon...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00924-07
更新日期:2008-01-01 00:00:00
abstract::Generally nonchemotactic mutants of Escherichia coli and Salmonella typhimurium were analyzed by interspecies complementation tests to determine the functional correspondence between the che genes of these two organisms. The E. coli che region was introduced into Salmonella recipients by means of a series of F-prime e...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.139.1.107-114.1979
更新日期:1979-07-01 00:00:00
abstract::In the long-chain n-alkane degrader Acinetobacter sp. strain M-1, two alkane hydroxylase complexes are switched by controlling the expression of two n-alkane hydroxylase-encoding genes in response to the chain length of n-alkanes, while rubredoxin and rubredoxin ruductase are encoded by a single gene and expressed con...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.5.1819-1823.2001
更新日期:2001-03-01 00:00:00
abstract::The genetics of antibiotic resistance in mutant strains of Streptococcus pyrogenes was studied. Utilizing a type 6 strain (9440) primarily resistant to strepttomycin (Strr), classes of mutant strains were isolated that were resistant to one of the following antibiotics: rifampin (Rifr), erythromycin (Eryr), thiostrept...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.133.2.852-859.1978
更新日期:1978-02-01 00:00:00
abstract::With two-dimensional restriction enzyme analysis we have been able to cleave the Bacillus subtilis genome and resolve the resulting deoxyribonucleic acid (DNA) segments into discrete bands on agarose gels. A general procedure for gene purification has been developed by coupling multidimensional restriction analysis wi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.129.1.492-500.1977
更新日期:1977-01-01 00:00:00
abstract::Salmonella typhimurium and Escherichia coli from anaerobic cultures displayed tactic responses to gradients of nitrate, fumarate, and oxygen when the appropriate electron transport pathway was present. Such responses were named "electron acceptor taxis" because they are elicited by terminal electron acceptors. Mutant ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.140.2.567-573.1979
更新日期:1979-11-01 00:00:00
abstract::Decreased intracellular levels of FtsH, a membrane-bound ATPase, led to retardation of growth and protein export, as well as to an abnormal translocation of alkaline phosphatase that had been attached to a cytoplasmic domain of a multispanning membrane protein, SecY. The last phenotype is designated Std (stop transfer...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.4.1141-1145.1996
更新日期:1996-02-01 00:00:00
abstract::A hydrocarbon-utilizing Brevibacterium which grew into the oil phase of an oil-water system was tested for survival at elevated temperature. Cells suspended in oil and cells that had been resuspended in aqueous solution were tested by placing 1-ml samples of the cell suspension in small test tubes immersed in a contro...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.116.3.1287-1292.1973
更新日期:1973-12-01 00:00:00
abstract:UNLABELLED:Pupylation is a posttranslational modification peculiar to actinobacteria wherein proteins are covalently modified with a small protein called the prokaryotic ubiquitin-like protein (Pup). Like ubiquitination in eukaryotes, this phenomenon has been associated with proteasome-mediated protein degradation in m...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00302-15
更新日期:2015-09-01 00:00:00
abstract::Harper, M. K. (U.S. Department of Agriculture, Washington, D.C.), H. R. Curran, and M. J. Pallansch. Properties of electrodialyzed bacterial spores. J. Bacteriol. 88:1338-1340. 1964.-Washed spores of Bacillus cereus, B. megaterium, and B. stearothermophilis suspended in distilled water were electrodialyzed at a potent...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.88.5.1338-1340.1964
更新日期:1964-11-01 00:00:00
abstract::Levy, Stuart B. (Institut du Radium, Paris, France). Isologous interference with ultraviolet and X-ray irradiated bacteriophage T(2). J. Bacteriol. 87:1330-1338. 1964.-Qualitative and quantitative analysis of the interference capacity of an irradiated T(2) bacteriophage was made with ultraviolet and X-ray irradiation....
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.87.6.1330-1338.1964
更新日期:1964-06-01 00:00:00
abstract::We have identified and characterized enzymes of phospholipid synthesis in two plasmalogen-rich anaerobes. Megasphaera elsdenii and Veillonella parvula, and one anaerobe lacking plasmalogens. Desulfovibrio vulgaris. All three species contained phosphatidate cytidylyltransferase and phosphatidylserine synthase. Phosphat...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.147.1.57-61.1981
更新日期:1981-07-01 00:00:00
abstract::Outer membrane preparations of Bdellovibrio bacteriovorus grown intraperiplasmically on Escherichia coli containing OmpF were prepared by the Triton X-100 procedure of Schnaitman (J. Bacteriol. 108:545-552, 1971). They contained a protein that migrated to almost the same position as E. coli OmpF in sodium dodecyl sulf...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.163.2.595-599.1985
更新日期:1985-08-01 00:00:00
abstract::Strains of Escherichia coli K12 have been prepared that carry the ruv mutation in combination with lon or uvrA mutant alleles. The ruv minus uvrA minus double mutant is more sensitive to ultraviolet light than the urvA minus single mutant, whereas the strain with ruv and ion mutations shows the same sensitivity to ult...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.121.2.735-736.1975
更新日期:1975-02-01 00:00:00
abstract::C(1), a lytic bacteriophage infecting group C streptococci, is one of the earliest-isolated phages, and the method of bacterial classification known as phage typing was defined by using this bacteriophage. We present for the first time a detailed analysis of this phage by use of electron microscopy, protein profiling,...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.185.11.3325-3332.2003
更新日期:2003-06-01 00:00:00
abstract::IS630 is a 1.15-kilobase sequence in Shigella sonnei that, unlike many mobile elements, seems not to mediate cointegration between different replicons. To assess its transposition, we constructed composite elements containing inverted copies of IS630 flanking a drug resistance gene. We found that these composite eleme...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.7.3830-3836.1990
更新日期:1990-07-01 00:00:00
abstract:UNLABELLED:Over the course of the last 3 decades the role of the second messenger cyclic di-GMP (c-di-GMP) as a master regulator of bacterial physiology was determined. Although the control over c-di-GMP levels via synthesis and breakdown and the allosteric regulation of c-di-GMP over receptor proteins (effectors) and ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00422-15
更新日期:2015-08-31 00:00:00
abstract::Four rpoD hybridizing signals have been identified in the chromosome of Brevibacterium lactofermentum. Two rpoD-like genes, sigA and sigB, have been cloned and sequenced, and they encode principal sigma factors of the RNA polymerase. The deduced amino acid sequences of SigA and SigB showed very high similarities to th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.2.550-553.1996
更新日期:1996-01-01 00:00:00
abstract::Mutants lacking an enzyme of the oxidative branch of the hexose monophosphate shunt, 6-phosphogluconolactonase (pgl), have been selected as a new class of glucose-negative derivatives of a phosphoglucose isomerase (pgi) mutant. Glucose negativity is not as complete as in mutants lacking phosphoglucose isomerase and gl...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.100.3.1296-1301.1969
更新日期:1969-12-01 00:00:00
abstract::Filaments of a thermosensitive Bacillus megaterium mutant showed an altered macromolecular composition compared with salt-cured mutant cells and parental cells. Filaments contained more peptidoglycan, polyglucose, poly-beta-hydroxy-butyrate, and deoxyribonucleic acid per unit of protein. The ribonucleic acid-to-protei...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.144.1.454-456.1980
更新日期:1980-10-01 00:00:00
abstract::Sbarra, Anthony J. (St. Margaret's Hospital, Boston, Mass.) and William Shirley. Phagocytosis inhibition and reversal. I. Effect of glycolytic intermediates and nucleotides on particle uptake. J. Bacteriol. 86:259-265. 1963.-By microscopically monitoring phagocytosis and following the biochemical changes associated wi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.86.2.259-265.1963
更新日期:1963-08-01 00:00:00
abstract::Rotation of the bacterial flagellar motor is powered by a transmembrane gradient of protons or, in some species, sodium ions. The molecular mechanism of coupling between ion flow and motor rotation is not understood. The proteins most closely involved in motor rotation are MotA, MotB, and FliG. MotA and MotB are trans...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.180.10.2729-2735.1998
更新日期:1998-05-01 00:00:00
abstract::Chlamydial lipopolysaccharide (LPS) agglutinated mouse and rabbit erythrocytes but not human, guinea pig, or pronghorn antelope erythrocytes. Hemagglutination was not specific for Chlamydia spp., as rough LPSs from Coxiella burnetii and Escherichia coli also agglutinated erythrocytes from the same animal species. Nona...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.8.3826-3828.1987
更新日期:1987-08-01 00:00:00