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Query: UMLS:C0043167 (
pertussis
)
19,595
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The putative chaperone-like protein ClpE, required for biogenesis of the Escherichia coli capsule-like antigen CS31A, was compared with ten known periplasmic chaperones from E. coli, Klebsiella pneumoniae, Bordetella
pertussis
, Haemophilus influenzae and
Yersinia
pestis. The amino acid sequence alignment was superimposed onto the three-dimensional structure of the PapD chaperone of uropathogenic E. coli, and amino acid residues involved in maintaining the structure integrity of the suggested binding site were found identical in most of the 11 chaperones. Construction of a phylogenetic tree to investigate the relationship within the chaperone family has revealed interesting degrees of relatedness between the different proteins.
...
PMID:The ClpE protein involved in biogenesis of the CS31A capsule-like antigen is a member of a periplasmic chaperone family in gram-negative bacteria. 809 76
Yersinia
pseudotuberculosis-derived mitogen (YPM) is the unique Gram-negative bacillary superantigen known. In order to identify the regions on the YPM molecule involved in its superantigenic activity, seven overlapping peptides of the entire YPM molecule were synthesized and tested to evaluate their effects on the YPM-induced proliferation of human peripheral blood lymphocytes. A peptide corresponding to the N-terminal amino acid sequence (1-23) was found to inhibit YPM-induced lymphocyte proliferation in a concentration-dependent manner. The N-terminal peptide was found to show no inhibition of the proliferation induced by the other superantigen (staphylococcal enterotoxin B) or the other T-cell mitogen
pertussis
toxin, indicating that the inhibition is specific to YPM-induced proliferation. Thus, we have identified the N-terminal region (1-23) of the YPM as one of the functional regions responsible for its superantigenic activity.
...
PMID:Identification of the functional region on the superantigen Yersinia pseudotuberculosis-derived mitogen responsible for induction of lymphocyte proliferation by using synthetic peptides. 870 58
Pathogenic yersiniae deliver a number of different effector molecules, which are referred to as Yops, into the cytosol of eukaryotic cells via a type III secretion system. To identify the regions of YopE from
Yersinia
pseudotuberculosis that are necessary for its translocation across the bacterial and eukaryotic cellular membranes, we constructed a series of hybrid genes which consisted of various amounts of yopE fused to the adenylate cyclase-encoding domain of the cyclolysin gene (cyaA) of Bordetella
pertussis
. By assaying intact cells for adenylate cyclase activity, we show that a YopE-Cya protein containing just the 11 amino-terminal residues of YopE is efficiently exported to the exterior surface of the bacterial cell. Single amino acid replacements of the first seven YopE residues significantly decreased the amount of reporter protein detected on the cell surface, suggesting that the extreme amino-terminal region of YopE is recognized by the secretion machinery. As has recently been shown for the Y. enterocolitica YopE protein (M.-P. Sory, A. Boland, I. Lambermont, and G. R. Cornelis, Proc. Natl. Acad. Sci. USA 92:11998-12002, 1995), we found that export to the cell surface was not sufficient for YopE-Cya proteins to be delivered into the eukaryotic cytoplasm. For traversing the HeLa cell membrane, at least 49 yopE-encoded residues were required. Replacement of leucine 43 of YopE with glycine severely affected the delivery of the reporter protein into HeLa cells. Surprisingly, export from the bacterial cell was also not sufficient for YopE-Cya proteins to be released from the bacterial cell surface into the culture supernatant. At least 75 residues of YopE were required to detect activity of the corresponding reporter protein in the culture supernatant, suggesting that a release domain exists in this region of YopE. We also show that the chaperone-like protein YerA required at least 75 YopE residues to form a stable complex in vitro with YopE-Cya proteins and, furthermore, that YerA is not required to target YopE-Cya proteins to the secretion complex. Taken together, our results suggest that traversing the bacterial and eukaryotic membranes occurs by separate processes that recognize distinct domains of YopE and that these processes are not dependent on YerA activity.
...
PMID:Delineation and mutational analysis of the Yersinia pseudotuberculosis YopE domains which mediate translocation across bacterial and eukaryotic cellular membranes. 895 6
By deletion mutagenesis in the entire meningococcal chromosome, we have previously identified the icsA gene, which encodes the glycosyltransferase required for adding GlcNAc to Hep-II in the inner core of meningococcal LPS. This gene has homology to several LPS glycosyltransferases, notably to rfaK from Salmonella typhimurium and bplH from Bordetella
pertussis
, both of which encode GlcNAc transferases. Directly upstream of icsA is an ORF showing significant homology to the hypothetical protein HI0653 from the Haemophilus influenzae genome sequence, and to a lesser degree to putative glycosyltransferases from Streptococcus thermophilus and
Yersinia
enterocolitica. Insertional inactivation of this ORF resulted in a meningococcal strain with truncated LPS. We have named this new LPS-involved gene icsB. Differences in binding of monoclonal antibodies and in mobility on Tricine-SDS-PAGE showed that LPS from icsA and icsB mutants is similar but not identical. On the basis of these results, we postulated that the new gene encodes the glycosyltransferase required for adding Glc to Hep-I. Structural analysis of purified mutant LPS by electrospray mass spectrometry was used to verify this hypothesis. The composition determined for icsA and icsB is lipidA-(KDO)2-(Hep)2.PEA and lipidA-(KDO)2-(Hep)2.PEA-GlcNAc, respectively. The icsA and icsB genes thus form an operon encoding the glycosyltransferases required for chain elongation from the lipidA-(KDO)2-(Hep)2 basal structure, with IcsA first adding GlcNAc to Hep-II and IcsB subsequently adding Glc to Hep-I. Only then is completion of the lacto-N-neotetraose structure possible through the action of the IgtA-E genes.
...
PMID:Analysis of the icsBA locus required for biosynthesis of the inner core region from Neisseria meningitidis lipopolysaccharide. 901 Oct 46
In Rhizobium etli CFN42, both the symbiotic plasmid (pd) and plasmid b (pb) are required for effective bean nodulation. This is due to the presence on pb of a region (lps beta) involved in lipopolysaccharide (LPS) biosynthesis. We report here the genetic array and functional features of this plasmid-borne region. The sequence analysis of a 3,595-bp fragment revealed the presence of a transcriptional unit integrated by two open reading frames (lps beta 1 and lps beta 2) essential for LPS biosynthesis and symblosis. The lps beta 1 encodes a putative 193 amino acid polypeptide that shows strong homology with glucosyl-1P and galactosyl-1P transferases. The deduced amino acid sequence of the protein encoded by lps beta 2 was very similar to that of proteins involved in surface polysaccharide biosynthesis, such as Pseudomonas aeruginosa WpbM, Bordetella
pertussis
BpIL, and
Yersinia
enterocolitica TrsG. DNA sequences homologous to lps beta 1 and lps beta 2 of R. etli CFN42 were consistently found in functionally equivalent plasmids of R. etli, R. leguminosarum bv. viciae, and R. leguminosarum hv. trifolii strains, but not in R. meliloti, R. loti, R. tropici, R. fredii, Bradyrhizobium, Azorhizobium, and Agrobacterium tumefaciens. Even though Rhizobium and Agrobacterium do not share lps beta sequences, their presence is required for crown-gall tumor induction by R. etli transconjugants carrying the Ti plasmid.
...
PMID:Characterization of two plasmid-borne lps beta loci of Rhizobium etli required for lipopolysaccharide synthesis and for optimal interaction with plants. 930 61
The BvgAS signal transduction system in Bordetella spp. mediates a transition between infectious (Bvg+) and non-infectious (Bvg-) phases by sensing environmental conditions and regulating gene expression. Using differential display, arbitrary-primed polymerase chain reaction (PCR), we identified a gene expressed in the Bvg+ phase of Bordetella bronchiseptica that shows a high degree of sequence similarity to a locus involved in providing energy for type III secretion in pathogenic gram-negative bacteria (yscN in
Yersinia
spp.). We determined that the expression of this homologue in B. bronchiseptica (designated bscN) is regulated by bvg. Several open reading frames surrounding the bscN locus also show sequence similarity to loci encoding type III secretion apparatus components in other bacteria. An in-frame deletion of bscN in B. bronchiseptica leads to decreased secretion of several proteins, decreased cytotoxicity towards cultured cell lines and a defect in causing tyrosine dephosphorylation of specific proteins in infected cells in vitro. The deletion strain also revealed that bscN-mediated secretion is required for persistent colonization of the trachea in a rat infection model. Loci encoding type III secretion homologues were identified in four strains of B.
pertussis
and two strains of B. parapertussis. B.
pertussis
strain 18323 and an ovine isolate of B. parapertussis show significant transcription of the genes in vitro.
...
PMID:The BvgAS virulence control system regulates type III secretion in Bordetella bronchiseptica. 966 81
We report the complete 119,443-bp sequence of the pgm locus from
Yersinia
pestis and its flanking regions. Sequence analysis confirms that the 102-kb unstable pgm locus is composed of two distinct parts: the pigmentation segment and a high-pathogenicity island (HPI) which carries virulence genes involved in iron acquisition (yersiniabactin biosynthetic gene cluster). Within the HPI, three genes coding for proteins related to phage proteins were uncovered. They are located at both extremities indicating that the entire HPI was acquired en bloc by phage-mediated horizontal transfer. We identified, within the pigmentation segment, two novel loci that may be involved in virulence: a fimbriae gene cluster and a locus probably encoding a two component regulatory system similar to the BvgAS regulatory system of Bordetella
pertussis
. Three genes containing frameshift mutations and two genes interrupted by insertion element insertion were found within this region. To investigate diversity among different Y. pestis and
Yersinia
pseudotuberculosis strains, the sequence of selected regions of the pgm locus and flanking regions were compared from 20 different Y. pestis and 10 Y. pseudotuberculosis strains. The results showed that the genes interrupted in Y. pestis are intact in Y. pseudotuberculosis. However, one of these mutations, in the bvgS homologue, is only present in Y. pestis strains of biovar Orientalis and not in those of the biovars Antiqua and Medievalis. The results obtained by analysis of variable positions in the sequence are in accordance with historical records, confirming that biovar Orientalis is the most recent lineage. Furthermore, sequence comparisons among 29
Yersinia
strains suggest that Y. pestis is a recently emerged pathogen that is probably entering the initial phase of reductive evolution.
...
PMID:The 102-kilobase pgm locus of Yersinia pestis: sequence analysis and comparison of selected regions among different Yersinia pestis and Yersinia pseudotuberculosis strains. 1045 41
Type III secretory genes(Bscl, J, K, L, N and O) have recently been identified in Bordetella bronchiseptica and shown to be under the control of the BvgAS locus. We examined a 35 616 byte DNA sequence amplified from Bordetella
pertussis
Tohama I for homology with known type III secretory genes in
Yersinia
spp. and Pseudomonas sppand a total of 20 homologous open reading frames were detected. Putative type III secretion proteins in B.
pertussis
were designated according to their homology with type III secretion proteins in B. bronchiseptica,
Yersinia
and Pseudomonas. These ORFs were arranged in two putative operons, which together we have designated as the BpeI locus. The first spans nucleotides 23385-7888 and encodes the putative proteins LcrH1, BopD, BopB, LcfH2, BscI, BscJ, BscK, BscL, BscN, BscO, BscQ, BscR, BscS, BscT, BscU, and BscC, in this order. The second spans nucleotides 23580-29863 and encodes the putative proteins LcrE, LcrD, BscD and BscF, in this order. The homology of these proteins to type III secretory proteins was B. bronchiseptica (73-99%),
Yersinia
spp. (17-65%), Pseudomonas spp. (18-64%). The B.
pertussis
proteins were similar to their homologues in B. bronchiseptica,
Yersinia
and Pseudomonas in terms of length, molecular weight and isoelectric point. Coiled-coil domains were detected in putative translocation proteins, BopB and BopD. BopB and BopD were similar to each other, to the RTX toxin family and to cyaA, cyaB, cyaD and cyaE. The percentage G+C content of the sequence analysed was 66.16%, which is similar to the published percentage G+C (67-70%) for the B.
pertussis
chromosome.
...
PMID:The Bpel locus encodes type III secretion machinery in Bordetella pertussis. 1058 8
The gene coding for the acetyl-CoA synthetase (ADP-forming) from the amitochondriate eukaryote Giardia lamblia has been expressed in Escherichia coli. The recombinant enzyme exhibited the same substrate specificity as the native enzyme, utilizing acetyl-CoA and adenine nucleotides as preferred substrates and less efficiently, propionyl- and succinyl-CoA. N- and C-terminal parts of the G. lamblia acetyl-CoA synthetase sequence were found to be homologous to the alpha- and beta-subunits, respectively, of succinyl-CoA synthetase. Sequence analysis of homologous enzymes from various bacteria, archaea, and the eukaryote, Plasmodium falciparum, identified conserved features in their organization, which allowed us to delineate a new superfamily of acyl-CoA synthetases (nucleoside diphosphate-forming) and its signature motifs. The representatives of this new superfamily of thiokinases vary in their domain arrangement, some consisting of separate alpha- and beta-subunits and others comprising fusion proteins in alpha-beta or beta-alpha orientation. The presence of homologs of acetyl-CoA synthetase (ADP-forming) in such human pathogens as G. lamblia,
Yersinia
pestis, Bordetella
pertussis
, Pseudomonas aeruginosa, Vibrio cholerae, Salmonella typhi, Porphyromonas gingivalis, and the malaria agent P. falciparum suggests that they might be used as potential drug targets.
...
PMID:Acetyl-CoA synthetase from the amitochondriate eukaryote Giardia lamblia belongs to the newly recognized superfamily of acyl-CoA synthetases (Nucleoside diphosphate-forming). 1068 68
Inorganic polyphosphate (poly P) is a chain of tens or many hundreds of phosphate (Pi) residues linked by high-energy phosphoanhydride bonds. Despite inorganic polyphosphate's ubiquity--found in every cell in nature and likely conserved from prebiotic times--this polymer has been given scant attention. Among the reasons for this neglect of poly P have been the lack of sensitive, definitive, and facile analytical methods to assess its concentration in biological sources and the consequent lack of demonstrably important physiological functions. This review focuses on recent advances made possible by the introduction of novel, enzymatically based assays. The isolation and ready availability of Escherichia coli polyphosphate kinase (PPK) that can convert poly P and ADP to ATP and of a yeast exopolyphosphatase that can hydrolyze poly P to Pi, provide highly specific, sensitive, and facile assays adaptable to a high-throughput format. Beyond the reagents afforded by the use of these enzymes, their genes, when identified, mutated, and overexpressed, have offered insights into the physiological functions of poly P. Most notably, studies in E. coli reveal large accumulations of poly P in cellular responses to deficiencies in an amino acid, Pi, or nitrogen or to the stresses of a nutrient downshift or high salt. The ppk mutant, lacking PPK and thus severely deficient in poly P, also fails to express RpoS (a sigma factor for RNA polymerase), the regulatory protein that governs > or = 50 genes responsible for stationary-phase adaptations to resist starvation, heat and oxidant stresses, UV irradiation, etc. Most dramatically, ppk mutants die after only a few days in stationary phase. The high degree of homology of the PPK sequence in many bacteria, including some of the major pathogenic species (e.g. Mycobacterium tuberculosis, Neisseria meningitidis, Helicobacter pylori, Vibrio cholerae, Salmonella typhimurium, Shigella flexneri, Pseudomonas aeruginosa, Bordetella
pertussis
, and
Yersinia
pestis), has prompted the knockout of their ppk gene to determine the dependence of virulence on poly P and the potential of PPK as a target for antimicrobial drugs. In yeast and mammalian cells, exo- and endopolyphosphatases have been identified and isolated, but little is known about the synthesis of poly P or its physiologic functions. Whether microbe or human, all species depend on adaptations in the stationary phase, which is truly a dynamic phase of life. Most research is focused on the early and reproductive phases of organisms, which are rather brief intervals of rapid growth. More attention needs to be given to the extensive period of maturity. Survival of microbial species depends on being able to manage in the stationary phase. In view of the universality and complexity of basic biochemical mechanisms, it would be surprising if some of the variety of poly P functions observed in microorganisms did not apply to aspects of human growth and development, to aging, and to the aberrations of disease. Of theoretical interest regarding poly P is its antiquity in prebiotic evolution, which along with its high energy and phosphate content, make it a plausible precursor to RNA, DNA, and proteins. Practical interest in poly P includes many industrial applications, among which is the microbial removal of Pi in aquatic environments.
...
PMID:Inorganic polyphosphate: a molecule of many functions. 1087 45
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