Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The prenyltransferase undecaprenyl pyrophosphate synthetase (di-trans,poly-cis-decaprenylcistransferase; EC 2.5.1.31) was purified from the soluble fraction of Escherichia coli by TSK-DEAE, ceramic hydroxyapatite, TSK-ether, Superdex 200, and heparin-Actigel chromatography. The protein was labeled with the photolabile analogue of the farnesyl pyrophosphate analogue (E, E)-[1-3H]-(2-diazo-3-trifluoropropionyloxy)geranyl diphosphate and was detected on a sodium dodecyl sulfate-polyacrylamide gel as a protein with an apparent molecular mass of 29 kDa. This protein band was cut out from the gel, trypsin digested, and subjected to matrix-assisted laser desorption ionization mass spectrometric analysis. Comparison of the experimental data with computer-simulated trypsin digest data for all E. coli proteins yielded a single match with a protein of unassigned function (SWISS-PROT Q47675; YAES_ECOLI). Sequences with strong similarity indicative of homology to this protein were identified in 25 bacterial species, in Saccharomyces cerevisiae, and in Caenorhabditis elegans. The homologous genes (uppS) were cloned from E. coli, Haemophilus influenzae, and Streptococcus pneumoniae, expressed in E. coli as amino-terminal His-tagged fusion proteins, and purified over a Ni2+ affinity column. An untagged version of the E. coli uppS gene was also cloned and expressed, and the protein purified in two chromatographic steps. We were able to detect Upp synthetase activity for all purified enzymes. Further, biochemical characterization revealed no differences between the recombinant untagged E. coli Upp synthetase and the three His-tagged fusion proteins. All enzymes were absolutely Triton X-100 and MgCl2 dependent. With the use of a regulatable gene disruption system, we demonstrated that uppS is essential for growth in S. pneumoniae R6.
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PMID:Use of genomics to identify bacterial undecaprenyl pyrophosphate synthetase: cloning, expression, and characterization of the essential uppS gene. 988 62

Here we describe the efficient synthesis of two oligosaccharide moieties of human glycosphingolipids, globotetraose (GalNAcbeta1-->3Galalpha1-->4Galbeta1-->4Glc) and isoglobotetraose (GalNAcbeta1-->3Galalpha1-->3Galbeta1-->4Glc), with in situ enzymatic regeneration of UDP-N-acetylgalactosamine (UDP-GalNAc). We demonstrate that the recombinant beta-1,3-N-acetylgalactosaminyltransferase from Haemophilus influenzae strain Rd can transfer N-acetylgalactosamine to a wide range of acceptor substrates with a terminal galactose residue. The donor substrate UDP-GalNAc can be regenerated by a six-enzyme reaction cycle consisting of phosphoglucosamine mutase, UDP-N-acetylglucosamine pyrophosphorylase, phosphate acetyltransferase, pyruvate kinase, and inorganic pyrophosphatase from Escherichia coli, as well as UDP-N-acetylglucosamine C4 epimerase from Plesiomonas shigelloides. All these enzymes were overexpressed in E. coli with six-histidine tags and were purified by one-step nickel-nitrilotriacetic acid affinity chromatography. Multiple-enzyme synthesis of globotetraose or isoglobotetraose with the purified enzymes was achieved with relatively high yields.
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PMID:Donor substrate regeneration for efficient synthesis of globotetraose and isoglobotetraose. 1240 59

Nickel, Lois (University of Pennsylvania, Philadelphia), and Sol H. Goodgal. Effect of interspecific transformation on linkage relationships of markers in Haemophilus influenzae and Haemophilus parainfluenzae. J. Bacteriol. 88:1538-1544. 1964.-Highly competent cells of Haemophilus parainfluenzae were obtained by a modification of the aerobic-"anaerobic" method of Goodgal and Herriott. The mutant markers for streptomycin and novobiocin resistance in H. parainfluenzae were shown to be unlinked. These same markers were transferred into H. influenzae in two transformation steps, and the deoxyribonucleic acid (DNA) was extracted. Transformation of recipient H. influenzae with DNA from the latter showed the markers to be linked, and transformation of recipient H. parainfluenzae with this DNA showed that the markers were not cotransferred. The linked streptomycin- and novobiocin-resistance mutations of H. influenzae were transformed into H. parainfluenzae in two stages, and the DNA was extracted. Transformation of recipient H. parainfluenzae with this DNA demonstrated the markers to be unlinked in H. parainfluenzae. When these markers, originally from H. influenzae and present as unlinked factors in H. parainfluenzae, are transferred back into H. influenzae, the markers showed their original linkage. The novobiocin- and erythromycin-resistance markers of H. influenzae were unlinked in H. influenzae, but were linked when transferred into H. parainfluenzae. The erythromycin-resistance marker of H. influenzae, when transferred into a novobiocin-resistant mutant of H. parainfluenzae, showed linkage with it. Evidence is presented to show that H. parainfluenzae streptomycin and novobiocin markers are homologous to streptomycin and novobiocin markers in H. influenzae.
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PMID:EFFECT OF INTERSPECIFIC TRANSFORMATION ON LINKAGE RELATIONSHIPS OF MARKERS IN HAEMOPHILUS INFLUENZAE AND HAEMOPHILUS PARAINFLUENZAE. 1424 Sep 34

Pathogenic Haemophilus influenzae, Neisseria spp. (Neisseria gonorrhoeae and N. meningitidis), Serratia marcescens, and other gram-negative bacteria utilize a periplasm-to-cytosol FbpABC iron transporter. In this study, we investigated the H. influenzae FbpABC transporter in a siderophore-deficient Escherichia coli background to assess biochemical aspects of FbpABC transporter function. Using a radiolabeled Fe3+ transport assay, we established an apparent Km=0.9 microM and Vmax=1.8 pmol/10(7)cells/min for FbpABC-mediated transport. Complementation experiments showed that hFbpABC is dependent on the FbpA binding protein for transport. The ATPase inhibitor sodium orthovanadate demonstrated dose-dependent inhibition of FbpABC transport, while the protonmotive-force-inhibitor carbonyl cyanide m-chlorophenyl hydrazone had no effect. Metal competition experiments demonstrated that the transporter has high specificity for Fe3+ and selectivity for trivalent metals, including Ga3+ and Al3+, over divalent metals. Metal sensitivity experiments showed that several divalent metals, including copper, nickel, and zinc, exhibited general toxicity towards E. coli. Significantly, gallium-induced toxicity was specific only to E. coli expressing FbpABC. A single-amino-acid mutation in the gene encoding the periplasmic binding protein, FbpA(Y196I), resulted in a greatly diminished iron binding affinity Kd=5.2 x 10(-4) M(-1), approximately 14 orders of magnitude weaker than that of the wild-type protein. Surprisingly, the mutant transporter [FbpA(Y196I)BC] exhibited substantial transport activity, approximately 35% of wild-type transport, with Km=1.2 microM and Vmax=0.5 pmol/10(7)cells/min. We conclude that the FbpABC complexes possess basic characteristics representative of the family of bacterial binding protein-dependent ABC transporters. However, the specificity and high-affinity binding characteristics suggest that the FbpABC transporters function as specialized transporters satisfying the strict chemical requirements of ferric iron (Fe3+) binding and membrane transport.
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PMID:The hFbpABC transporter from Haemophilus influenzae functions as a binding-protein-dependent ABC transporter with high specificity and affinity for ferric iron. 1534 92

We have cloned the rpoZ gene, encoding RNA polymerase omega protein, by PCR approach from the deep-sea piezophilic and psychrophilic bacterium, Shewanella violacea strain DSS12. The cloned gene, 285bp in length, was found to encode a protein consisting of 94 amino acid residues with a molecular mass of 10,327 Da. Significant homology was evident comparing the RpoZ protein of S. violacea with that of Shewanella oneidensis (69% identity), Vibrio cholerae (65% identity), Escherichia coli K-12 (64% identity) and Haemophilus influenzae (61% identity). From the Northern blot analysis, S. violacea rpoZ gene was expressed constitutively under pressure conditions of 0.1, 30 and 50MPa. We constructed expression plasmid to overproduce the RpoZ protein and transformed into E. coli JM109 as a host of overproduction. Upon induction, the recombinant protein encoded by plasmid pQrpoZ was overexpressed and purified using Ni2+ affinity column.
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PMID:Cloning and overproduction of the rpoZ gene encoding an RNA polymerase omega subunit from a deep-sea piezophilic Shewanella violacea strain DSS12. 1534 66

Cobalt(II), nickel(II), copper(II) and zinc(II) complexes of 2-thiophenecarbonyl and isonicotinoyl hydrazones of 3-(N-methyl)isatin (HL(1) and HL(2), respectively) were synthesized and characterized, being the crystal structures of HL(1), HL(2) and [Ni(L(1))(2)].2CHCl(3) elucidated by X-ray diffraction techniques. The in vitro antimicrobial activity of all these compounds was tested against several bacteria and fungi. HL(1)and its complexes exhibited a strong inhibition of the growth of Haemophilus influenzae (MIC 0.15-1.50microg/mL) and good antibacterial properties towards Bacillus subtilis (MIC 3-25microg/mL). The minimal inhibitory concentration (MIC) was defined as the lowest concentration of compound inhibiting the growth of each strain. The antibacterial effectiveness was confirmed against a number of Gram positive bacteria, including methicillin-resistant Staphylococcus aureus. Yeasts and moulds showed a low susceptibility, except the dermatophyte mould Epidermophyton floccosum that is inhibited at concentrations ranging from 6 to 50microg/mL. In general, the antimicrobial activity of the thiophene derivatives was greater than that of the isonicotinic analogues.
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PMID:Complexes of 2-thiophenecarbonyl and isonicotinoyl hydrazones of 3-(N-methyl)isatin. A study of their antimicrobial activity. 1707 Sep 19

Cobalt, nickel, copper and zinc coordination compounds of two thiosemicarbazones with general composition ML(2) (L: monodeprotonated ligand corresponding to 2-acetyl-gamma-butyrolactone thiosemicarbazone, HL(1), and 2-furancarbaldehyde thiosemicarbazone, HL(2)) and also complexes with general composition MCl(2)(HL(2)) were synthesized (except [NiCl(2)(HL(2))] and [Co(L(2))(2)]). The interaction of CuCl(2) with HL(2) gave [CuCl(HL(2))], a copper(I) complex. The ligands and metal complexes were characterized by IR, (1)H and (13)C NMR spectroscopy, and magnetic susceptibility measurements. The crystal structure of [Ni(L(2))(2)]x 2dmso was determined and a trans-square planar coordination of the two kappa(2)-N,S chelate rings forming polymeric strips through H-bonds with dmso was observed. Actually, in all the reported complexes both ligands behaved as kappa(2)-N,S chelates, except in the case of [Co(L(1))(2)] in which HL(1) is tridentate kappa(3)-N,S,O. The antimicrobial properties of all compounds were studied using a wide spectrum of bacterial and fungal strains. The copper complexes of HL(2) were the most active against all strains, including dermatophytes and phytopathogenic fungi. Most of the studied compounds, especially [Cu(L(1))(2)], presented good activity against Haemophilus influenzae, a very harmful bacterium to humans.
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PMID:Complexes of 2-acetyl-gamma-butyrolactone and 2-furancarbaldehyde thiosemicarbazones: antibacterial and antifungal activity. 1894 78

We have identified a novel regulator from the MerR family of transcription factors in the bacterial pathogen Haemophilus influenzae (HI1623; nickel-associated merR-like Regulator--NimR). NimR regulates the expression of a Ni(2+) uptake transporter (NikKLMQO). The promoters for nimR and the nik operon are divergent and overlapping and NimR binds at a site between the promoter elements for nikKLMQO. Expression of this operon requires NimR and depends on Ni(2+). Growth rates of the H. influenzae nimR and nikQ mutants were reduced in chemically defined media compared to the wild type and the mutants were unable to grow in the presence of EDTA. The mutant strains were less tolerant of acidic pH and the wild type Rd KW20 could not tolerate low pH in the presence of fluoramide, a urease specific inhibitor, confirming that both nickel transport and urea hydrolysis are a central process in pH control. H. influenzae nimR and nikQ strains were deficient in urease activity, but this could be specifically restored by the addition of excess Ni(2+). NimR did not directly regulate the expression of urease genes but the activity of urease requires both nimR and nikQ. Purified NimR is a dimer that binds 1 Ni(2+)ion. NimR is the first example of a Ni-dependent regulator from the MerR family and targeting a metal ion uptake system; it is distinct from NikR the Ni-responsive regulators of the ribbon-helix-helix family.
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PMID:A novel nickel responsive MerR-like regulator, NimR, from Haemophilus influenzae. 2195 67

Of the known proteins which use nickel as a co-factor, Haemophilus influenzae contains only urease and glyoxalase I (gloA). We have recently reported that this pathogen harbours a unique nickel uptake system (nikKLMQO-nimR). Unusually, the disruption of the nickel uptake system (nikQ or nimR mutants) resulted in cells that aggregated and formed an increased biofilm compared to the wild type cells. Using a gloA mutant strain and urease-specific inhibitor we showed that this phenotype is not due to the loss-of-function of these enzymes. By generating H. influenzae "resting cells" which are enzymatically inactive but maintain their structural integrity we have shown that the cell aggregation in the nikQ/nimR mutants is not due to the loss of enzymatic function. The nikQ mutant was unable to accumulate nickel but the addition of excess nickel did restore intracellular nickel levels and this resulted in the nikQ mutant returning to the wild type "free-living" phenotype; cells with no aggregation and no biofilm formation. We used a range of techniques which showed that the nikQ mutant possesses changes to its cell surface properties. The mutant was more negatively charged than wild type cells as well as being more hydrophobic. Analysis of the outer membrane constituents showed that there were molecular differences. Although the nikQ mutant appears to grow the same as its wild type cell we have shown that there is a change in the "lifestyle" of these nickel limited cells and this induces changes to the surface of the cell to promote cell-cell aggregation and biofilm formation.
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PMID:The concentration of intracellular nickel in Haemophilus influenzae is linked to its surface properties and cell-cell aggregation and biofilm formation. 2349 78

Nickel acts as a co-factor for a small number of enzymes in bacteria. Urease is one of the two nickel-dependent enzymes that have been identified in Haemophilus influenzae; glyoxalase I is the other. However, nickel has been suggested to have roles in H. influenzae that can not attributed to the function of these enzymes. We have previously shown that in the H. influenzae strain Rd KW20 the inability to acquire nickel led to alterations to the cell-type; an increased biofilm formation and changes in cell surface properties. Here we report the differences in the genome wide gene expression between Rd KW20 and a strain incapable of importing nickel (nikQ); revealing a link between intracellular nickel levels and genes involved in metabolic pathways, stress responses and genes associated with surface factors such as type IV pili. We have then taken a strain previously shown to use type IV pili both in biofilm formation and for twitching motility (86-028NP) and have shown its homologous genes (NTHI1417-1422; annotated as cobalt transporter, cbiKLMOQ) did import nickel and mutations in this locus had pleiotropic effects correlating to stress response and motility. Compared to wild type cells, the nickel depleted cells were more electronegativity charged, they aggregated and formed a biofilm. Correct intracellular nickel levels were also important for resistance to oxidative stress; the nickel depleted cells were more sensitive to oxidative stress. The nickel depleted cells were also non-motile, but the addition specifically of nickel returned these cells to a wild type motility state. We have also analysed the role of nickel uptake in a naturally, urease negative strain (the blood isolate R2866) and depleting intracellular nickel (a nikQ mutant) in this strain effected a similar range of cell functions. These data reveal a role for the capacity to acquire nickel from the environment and for the correct intracellular nickel levels as part of H. influenzae stress response and in signalling for a switch to a sessile bacterial lifestyle.
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PMID:A new insight into the role of intracellular nickel levels for the stress response, surface properties and twitching motility by Haemophilus influenzae. 2535 Jan 48


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