Abstract:
:Group B streptococci (GBS) represent a very important group of human pathogens. So far little is known about the mechanisms by which these bacteria can cause disease and the bacterial factors involved. One putative virulence factor is the beta antigen of the C protein complex (Bac), which can bind to the Fc region of human IgA. Its binding function might represent an important virulence mechanism. However, the genetic manipulation of this group of bacteria, necessary to prove involvement of bacterial factors in pathogenesis, is still in its infancy. We therefore tested the pAM401 vector system for its suitability in the construction of a heterologous expression mutant using the Bac protein as a model antigen. The bac gene, including its own promoter, was cloned into the Escherichia coli-Enterococcus faecalis shuttle vector pAM401 and was stably maintained extrachromosomally in the bac-deficient GBS strain 335. Expression of Bac was assessed by extracting the protein from transformed 335(pPJTU1) cells, negative controls (335 wild-type, 335(pAM401)) and other Bac-expressing GBS strains (A909, LA239). Blots of the extracted proteins probed with IgA, polyclonal sera and a monoclonal antibody raised against Bac clearly revealed expression of the 130-kDa protein in the transformed GBS 335(pPJTU1) cells. The correct processing and surface anchoring of the expressed Bac was demonstrated by binding of (125)I-labelled IgA to whole cells. Strain 335(pPJTU1) bound 12 times as much IgA compared to the parental strain LA239 and the GBS 335 negative controls, and a total of 25% compared to the high-level-expressing strain A909. Our studies show that the pAM401 shuttle vector can be used for stable heterologous expression of surface proteins in GBS. Our strategy is also of major importance for the complementation of deletion mutants in GBS and other Gram-positive human pathogens to fulfill Koch's postulates. The Bac mutant constructed in this study, 335(pPJTU1), can be used in animal models to assess the importance of Bac in GBS pathogenesis.
journal_name
FEMS Microbiol Lettjournal_title
FEMS microbiology lettersauthors
Kreikemeyer B,Jerlström PGdoi
10.1111/j.1574-6968.1999.tb08804.xkeywords:
subject
Has Abstractpub_date
1999-11-15 00:00:00pages
255-62issue
2eissn
0378-1097issn
1574-6968pii
S0378-1097(99)00496-6journal_volume
180pub_type
杂志文章abstract::Mycobacteria belonging to the Mycobacterium tuberculosis complex have the ability to invade and replicate in non-phagocytic cells, an event that requires the presence of bacterial surface components capable of triggering a cell response and the subsequent internalization of the microorganism. In this study, we report ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1999.tb13738.x
更新日期:1999-08-15 00:00:00
abstract::A DNA microarray was used to analyze the distribution of plasmid and chromosomal genes among strains of enteroaggregative Escherichia coli (EAEC) isolated from a prospective diarrhoea surveillance study in the United Kingdom. Target genes were extracted from existing databases and from the genome sequence of prototype...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/j.femsle.2005.09.040
更新日期:2005-12-01 00:00:00
abstract::In this report we describe the development of a highly stringent and dually regulated promoter system for Shigella flexneri. Dual regulation was provided by utilizing a promoter susceptible to control by the bacteriophage P1 temperature-sensitive C1 repressor that in turn was under the transcriptional control of LacI....
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2002.tb11396.x
更新日期:2002-10-08 00:00:00
abstract::Streptococcus bovis HC5 cultures released a broad spectrum lantibiotic, bovicin HC5, into the cell-fee culture supernatant after they reached stationary phase, but most of the antibacterial activity remained cell-associated. Cell-associated bovicin HC5 was more resistant to degradation by Pronase E than the cell-free ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2008.01155.x
更新日期:2008-06-01 00:00:00
abstract::Insertion sequence IS100 was localized on a 9.5-kb plasmid of Yersinia pestis and was shown to be specific for Y. pestis and serotype I strains of Y. pseudotuberculosis. The nucleotide sequence of IS100 isolated from this plasmid was determined. The element, which was flanked by 5-bp direct repeats, contained 1953 bp ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1994.tb07111.x
更新日期:1994-09-01 00:00:00
abstract::Five mutations in ccpA of Bacillus megaterium with impaired functions were analysed for carbon catabolite repression. The phenotypes support the hypothesis that CcpA assumes a PurR/LacI fold. The completely inactive mutants CcpA119GE and CcpA326am cause alterations which are incompatible with that fold. A mutation wit...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1997.tb10485.x
更新日期:1997-08-01 00:00:00
abstract::The virulence of Salmonella typhimurium for mice is dependent on a plasmid-borne gene cluster termed spv. We previously determined that both S. typhimurium and Escherichia coli bacteria grown in a rich medium preferentially express the spv genes during the stationary phase of growth. In this study we evaluated the rol...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/0378-1097(92)90039-q
更新日期:1992-12-01 00:00:00
abstract::A number of hybrids obtained by fusion of protoplasts of complementary auxotrophic strains of Candida albicans were analysed for growth rates, cell volume, DNA content, stability and adherence to human buccal epithelial cells. SDS-PAGE analysis of the cell wall proteins indicated that the hybrid cell walls contained m...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1994.tb06617.x
更新日期:1994-01-01 00:00:00
abstract::The commercialization of the n-butanol bioprocess is largely dependent on the price of feedstocks. Renewable cellulose appears to be an appealing feedstock. The microbial production of n-butanol still remains challenging because of the limited availability of intracellular NADH. To address this issue, an Escherichia c...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1093/femsle/fnw008
更新日期:2016-02-01 00:00:00
abstract::The American Society for Microbiology's curricular guidelines for Introductory Microbiology highlighted key laboratory skills in the isolation, visualization and identification of microorganisms as core learning objectives in the discipline. Since the publication of these guidelines in 2012, there has been a paucity o...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1093/femsle/fny224
更新日期:2018-10-01 00:00:00
abstract::Staphylococcus aureus is responsible for a broad variety of chronic infections. Most S. aureus clinical isolates show the capacity to adhere to abiotic surfaces and to develop biofilms. Because S. aureus growing in a biofilm is highly refractory to treatment, inhibition of biofilm formation represents a major therapeu...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2008.01316.x
更新日期:2008-10-01 00:00:00
abstract::Streptomyces coelicolor A3(2) produces an antibiotic, actinorhodin, which belongs to the aromatic polyketides and which can function as an acid/base indicator. Its production results in the death of microorganisms in the vicinity of S. coelicolor A3(2), and this phenomenon can be used in concert with biopesticides. Th...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2006.00531.x
更新日期:2007-01-01 00:00:00
abstract::Klebsiella aerogenes W70 was reported previously to produce a membrane-associated tyramine oxidase (TynA) that did not act on 2-phenylethylamine. Subsequently, a gene cloned from K. aerogenes W70 produced a soluble amine oxidase (MaoA) that acted readily on 2-phenylethylamine and tyramine. This enzyme appeared to be e...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1997.tb10175.x
更新日期:1997-01-01 00:00:00
abstract::The effects of specific inhibitors of glycoprotein trimming reactions on Junin virus (JV) replication were investigated. Bromoconduritol, an inhibitor of glucosidase II, significantly reduced infective virus production (DE50: 1.1 mM) and viral protein expression. Neither 1-deoxynojirimycin, an inhibitor of both glucos...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1993.tb06140.x
更新日期:1993-05-01 00:00:00
abstract::A 3.5-kb native plasmid (pND103) was identified in Streptococcus thermophilus ST2-1. Preliminary sequence analysis indicated that pND103 belongs to group I S. thermophilus plasmids. A region of approximately 2 kb appears to contain three components: a plus origin of replication (ori) typical of plasmids that replicate...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2002.tb11412.x
更新日期:2002-10-29 00:00:00
abstract::The Tat machinery catalyzes the transport of folded proteins across the cytoplasmic membrane in bacteria and the thylakoid membrane in plants. Transport occurs only in the presence of an electric field (Δψ) and/or a pH (ΔpH) gradient, and thus, Tat transport is considered to be dependent on the proton motive force (pm...
journal_title:FEMS microbiology letters
pub_type: 杂志文章,评审
doi:10.1093/femsle/fny123
更新日期:2018-06-01 00:00:00
abstract::Two Pseudomonas aeruginosa genes, termed phaJ1(Pa) and phaJ2(Pa), homologous to the Aeromonas caviae (R)-specific enoyl-CoA hydratase gene (phaJ(Ac)) were cloned using a PCR technique to investigate the monomer-supplying ability for polyhydroxyalkanoate (PHA) synthesis from beta-oxidation cycle. Two expression plasmid...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2000.tb09013.x
更新日期:2000-03-15 00:00:00
abstract::The hypA-E operon is involved in the maturation of all three NiFe hydrogenases in Escherichia coli. Two hyp promoters have been described; a sigma54-dependent promoter upstream of hypA, and a sigma70-dependent promoter (PhypA) within the hypA coding region. Here it is shown that the oxygen-responsive transcription fac...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/S0378-1097(03)00726-2
更新日期:2003-11-07 00:00:00
abstract::Francisella tularensis is a highly virulent bacterial species that causes various forms of tularemia in humans. The urgency in understanding the pathogenesis of these diseases has stimulated unprecedented interest in this bacterial species over the past few years. Recent findings underscore a number of important disti...
journal_title:FEMS microbiology letters
pub_type: 杂志文章,评审
doi:10.1111/j.1574-6968.2009.01791.x
更新日期:2009-11-01 00:00:00
abstract::We have previously reported that mycolyl glycolipids from Nocardia rubra such as glucose or trehalose mycolates induced granuloma formation in mice. The structure of the carbohydrate moiety of the mycolyl glycolipids influenced the granuloma forming activity profoundly. Here, we have examined the macrophage-chemotacti...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/0378-1097(90)90166-n
更新日期:1990-01-15 00:00:00
abstract::Acinetobacter baumannii is an important nosocomial pathogen that displays high antibiotic resistance. It causes a variety of infections including pneumonias and sepsis which may result in disseminated intravascular coagulation. In this work, we identify and characterize a novel secreted, zinc-dependent, metallo-endope...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/1574-6968.12496
更新日期:2014-07-01 00:00:00
abstract::In several bacterial species that show natural transformation, dprA has been described as a competence gene. The DprA protein has been suggested to be involved in the protection of incoming DNA. However, members of the dprA gene family (also called smf) can be detected in virtually all bacterial species, which suggest...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2006.00423.x
更新日期:2006-10-01 00:00:00
abstract::The flaA gene, which codes for the Spirochaeta aurantia flagellar filament outer layer polypeptide, FlaA, was cloned, sequenced and analysed. The gene appears to be transcribed into a monocistronic mRNA from a sigma 70-like promoter. The translational start is 31 base pairs after the start of the transcript, the open ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1993.tb05971.x
更新日期:1993-02-01 00:00:00
abstract::The effects of overexpression of the apurinic/apyrimidinic DNA endonuclease Nfo on wet and dry heat and UV-C (254 nm) resistance of Bacillus subtilis spores with or without alpha/beta-type small, acid-soluble spore proteins (SASP) were determined. Results revealed that overexpression of Nfo > or =50-fold in spores inc...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2009.01845.x
更新日期:2010-01-01 00:00:00
abstract::An identification method by PCR, specific to the Carnobacterium genus, was optimised by testing it on 28 bacterial strains. Primers from the literature were tested to differentiate Carnobacterium strains present among various bacterial species. The DNA of Carnobacterium species (C. alterfunditum, C. divergens, C. fund...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/j.femsle.2005.05.037
更新日期:2005-09-01 00:00:00
abstract::A chromosomal DNA fragment from Streptomyces antibioticus ATCC11891 was isolated by its ability to stimulate actinorhodin and undecylprodigiosin biosynthesis in Streptomyces lividans TK21. This fragment includes two open reading frames, whose deduced translated products resemble enzymes involved in sulfur metabolism (...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1997.tb10216.x
更新日期:1997-02-01 00:00:00
abstract::A suite of six sterols, lanosterol, lanost-8(9)-en-3beta-ol, 4, 4-dimethylcholesta-8(14),24-dien-3beta-ol, 4, 4-dimethylcholest-8(14)-en-3beta-ol, 4-methylcholesta-8(14), 24-dien-3beta-ol and 4-methylcholest-8(14)-en-3beta-ol, were identified in the psychrophilic methanotrophic bacterium, Methylosphaera hansonii. Thei...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2000.tb09103.x
更新日期:2000-05-15 00:00:00
abstract::The stable carbon isotopic compositions of the inorganic carbon source, bulk cell material, and isoprenoid lipids of the hyperthermophilic crenarchaeon Metallosphaera sedula, which uses a 3-hydroxypropionate-like pathway for autotrophic carbon fixation, have been measured. Bulk cell material was approximately 3 per th...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2001.tb10542.x
更新日期:2001-03-01 00:00:00
abstract::L-arginine has attracted a great deal of attention as an agent for refolding denatured proteins, and the mildness of its effects offer hope for a wide range of potential applications for this substance, including medicines with few side effects. We report that both L- and D-arginine inhibits Na+-driven flagellar motor...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2006.00117.x
更新日期:2006-03-01 00:00:00
abstract::We have cloned and sequenced the rfaH gene from Salmonella enterica serovar Typhi strain Ty2. The gene showed a high degree of similarity to the rfaH genes from Escherichia coli K-12 and S. enterica serovar Typhimurium. A rfaH mutant was constructed by site-directed mutagenesis. This mutant produced a rough lipopolysa...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2001.tb10874.x
更新日期:2001-10-16 00:00:00