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

We report DNA and predicted protein sequence similarities, implying homology, among genes of double-stranded DNA (dsDNA) bacteriophages and prophages spanning a broad phylogenetic range of host bacteria. The sequence matches reported here establish genetic connections, not always direct, among the lambdoid phages of Escherichia coli, phage phiC31 of Streptomyces, phages of Mycobacterium, a previously unrecognized cryptic prophage, phiflu, in the Haemophilus influenzae genome, and two small prophage-like elements, phiRv1 and phiRv2, in the genome of Mycobacterium tuberculosis. The results imply that these phage genes, and very possibly all of the dsDNA tailed phages, share common ancestry. We propose a model for the genetic structure and dynamics of the global phage population in which all dsDNA phage genomes are mosaics with access, by horizontal exchange, to a large common genetic pool but in which access to the gene pool is not uniform for all phage.
 ...
PMID:Evolutionary relationships among diverse bacteriophages and prophages: all the world's a phage. 1005 17

The DNA repair protein RecA of Mycobacterium tuberculosis contains an intein, a self-splicing protein element. We have employed this Mtu recA intein to create a selection system for successful intein splicing by inserting it into a kanamycin-resistance gene so that functional antibiotic resistance can only be restored upon protein splicing. We then proceeded to develop an ORFTRAP, i.e., a selection system for the cloning of open reading frames (ORFs). The ORFTRAP exploits the self-splicing properties of inteins (which depend on full-length in-frame translation of a precursor protein) by allowing protein splicing to occur when DNA fragments encoding ORFs are inserted into the Mtu recA intein, whereas DNA fragments containing non-ORFs are selected against. Regions of the Mtu recA intein that tolerate the insertion of additional amino acids were identified by Bgl II linker scanning mutagenesis, and a respective construct was chosen as the ORFTRAP. To test the maximum insert size that could be cloned into ORFTRAP, DNA fragments of increasing length from the Listeria monocytogenes hly gene as well as a genomic library of Haemophilus influenzae were inserted and it was found that the longest permissive inserts were 425 bp and 251 bp, respectively. The H. influenzae ORFTRAP library also demonstrated the strength (strong selection power) and weakness (insertion of very small fragments) of the system. Further modifications should make the ORFTRAP useful for protein expression, epitope mapping, and antigen screening.
 ...
PMID:The Mycobacterium tuberculosis recA intein can be used in an ORFTRAP to select for open reading frames. 1009 67

The in vitro and in vivo activities of T-3811ME, a novel des-F(6)-quinolone, were evaluated in comparison with those of some fluoroquinolones, including a newly developed one, trovafloxacin. T-3811, a free base of T-3811ME, showed a wide range of antimicrobial spectra, including activities against Chlamydia trachomatis, Mycoplasma pneumoniae, and Mycobacterium tuberculosis. In particular, T-3811 exhibited potent activity against various gram-positive cocci, with MICs at which 90% of the isolates are inhibited (MIC90s) of 0.025 to 6.25 microgram/ml. T-3811 was the most active agent against methicillin-resistant Staphylococcus aureus and streptococci, including penicillin-resistant Streptococcus pneumoniae (PRSP). T-3811 also showed potent activity against quinolone-resistant gram-positive cocci with GyrA and ParC (GrlA) mutations. The activity of T-3811 against members of the family Enterobacteriaceae and nonfermentative gram-negative rods was comparable to that of trovafloxacin. In common with other fluoroquinolones, T-3811 was highly active against Haemophilus influenzae, Moraxella catarrhalis, and Legionella sp., with MIC90s of 0.0125 to 0.1 microgram/ml. T-3811 showed a potent activity against anaerobic bacteria, such as Bacteroides fragilis and Clostridium difficile. T-3811 was the most active agent against C. trachomatis (MIC, 0.008 microgram/ml) and M. pneumoniae (MIC90, 0.0313 microgram/ml). The activity of T-3811 against M. tuberculosis (MIC90, 0.0625 microgram/ml) was potent and superior to that of trovafloxacin. In experimental systemic infection with a GrlA mutant of S. aureus and experimental pneumonia with PRSP in mice, T-3811ME showed excellent therapeutic efficacy in oral and subcutaneous administrations.
 ...
PMID:In vitro and in vivo antimicrobial activities of T-3811ME, a novel des-F(6)-quinolone. 1022 17

The performance of the GeneScan algorithm for gene identification has been improved by incorporation of a directed iterative scanning procedure. Application is made here to the cases of bacterial and organnellar genomes. The sensitivity of gene identification was 100% in Plasmodium falciparum plastid-like genome (35 kb) and in 98% in the Mycoplasma genitalium genome (approximately 580 kb) and the Haemophilus influenzae Rd genome (approximately 1.8 Mb). Sensitivity was found to improve in both the Open Reading Frames (ORFs) which have been identified as genes (by homology or by other methods) and those that are classified as hypothetical. False positive assignments (at the nucleotide level) were 0.25% in H. influenzae genome and 0.3% in M. genitalium. There were no false positive assignments in the plastid-like genome. The agreement between the GeneScan predictions and GeneMark predictions of putative ORFs was 97% in M. genitalium genome and 86% in H. influenzae genome. In terms of an exact match between predicted genes/ORFs and the annotation in the databank, GeneScan performance was evaluated to be between 72% and 90% in different genomes. We predict five putative ORFs that were not annotated earlier in the GenBank files for both M. genitalium and H. influenzae genomes. Our preliminary analysis of the newly sequenced G + C rich genome of Mycobacterium tuberculosis H37Rv also shows comparable sensitivity (99%).
 ...
PMID:Gene identification in bacterial and organellar genomes using GeneScan. 1035 88

An approach based on the 16 S rDNA polymerase chain reaction (16S PCR) and oligoprobe hybridization was applied to 77 cerebrospinal fluid samples submitted to the clinical microbiology laboratory for culture. Broad-range 16S rDNA primers were selected in conserved regions of the gene. Oligoprobes specific for Neisseria meningitidis, Haemophilus influenzae, Streptococcus spp., and Mycobacterium tuberculosis were selected in specific variable regions of the amplified 600 base pairs (bp) in the 16S rDNA. None of the oligoprobes cross hybridized with DNA from the other bacteria or from common contaminants. There were no false-negative results in culture-positive cerebrospinal fluid samples. Ten cases of meningitis caused by bacteria other than the four probes were not identified by any of the four probes. In culture-negative cerebrospinal fluid samples with some abnormal chemical parameters, there were 14 amplicons -- one of Haemophilus influenzae, three of Streptococcus spp., six of Mycobacterium tuberculosis, and four not identified -- while in normal cerebrospinal fluid samples there were no amplicons.
 ...
PMID:Use of oligoprobes on amplified DNA in the diagnosis of bacterial meningitis. 1042 Oct 43

We examined codon usage in Bacillus subtilis genes by multivariate analysis, quantified its cellular levels of individual tRNAs, and found a clear constraint of tRNA contents on synonymous codon choice. Individual tRNA levels were proportional to the copy number of the respective tRNA genes. This indicates that the tRNA gene copy number is an important factor to determine in cellular tRNA levels, which is common with Escherichia coli and yeast Saccharomyces cerevisiae. Codon usage in 18 unicellular organisms whose genomes have been sequenced completely was analyzed and compared with the composition of tRNA genes. The 18 organisms are as follows: yeast S. cerevisiae, Aquifex aeolicus, Archaeoglobus fulgidus, B. subtilis, Borrelia burgdorferi, Chlamydia trachomatis, E. coli, Haemophilus influenzae, Helicobacterpylori, Methanococcusjannaschii, Methanobacterium thermoautotrophicum, Mycobacterium tuberculosis, Mycoplasma genitalium, Mycoplasma pneumoniae, Pyrococcus horikoshii, Rickettsia prowazekii, Synechocystis sp., and Treponema pallidum. Codons preferred in highly expressed genes were related to the codons optimal for the translation process, which were predicted by the composition of isoaccepting tRNA genes. Genes with specific codon usage are discussed in connection with their evolutionary origins and functions. The origin and terminus of replication could be predicted on the basis of codon usage when the usage was analyzed relative to the transcription direction of individual genes.
 ...
PMID:Studies of codon usage and tRNA genes of 18 unicellular organisms and quantification of Bacillus subtilis tRNAs: gene expression level and species-specific diversity of codon usage based on multivariate analysis. 1057 Sep 92

A series of complete bacterial genome sequences have recently become available and powerful methods have been developed for the identification of tandem repeats on a very large scale. It is thus possible to derive extensive comparative descriptions of such repeats at the level of complete genomes, as illustrated here for three different bacterial genomes: Escherichia coli, Haemophilus influenzae, and Mycobacterium tuberculosis. Such sequence analyses can be usefully complemented by structural characterisations of the repeats.
 ...
PMID:Tandem repeats in complete bacterial genome sequences: sequence and structural analyses for comparative studies. 1067 12

The genomes of Methanococcus jannaschii, Mycoplasma genitalium, Haemophilus influenzae, Archaeoglobus fulgidus, Helicobacter pylori, Treponema pallidum, Borrelia burgdorferri, Rickettsia prowazekeii, Mycobacterium tuberculosis, Methanobacterium thermoautotrophicum, Synechocystis sp. PCC6803, Bacillus subtilis, Chlamydia trachomatis, Pyrococcus horikoshii, Aquifex aeolicus, Mycoplasma pneumoniae and Escherichia coli have been analysed for the presence of polypurine.polypyrimidine tracts, in order to understand their distribution in these genomes. We observed a variation in abundance of such sequences in these bacteria, with the archaeal genomes forming a high-abundance group and the canonical eubacteria forming a low-abundance group. The genomes of M. tuberculosis and A. aeolicus are unique among the organisms analysed here in the abnormal underrepresentation and overrepresentation of polypurine.polypyrimidine, respectively. We also observe a strand bias, i.e., a preferential occurrence of polypurines in coding strands. It varies widely among the bacteria, from the very high bias in M. jannaschii to the slightly inverse bias in the parasitic genomes of T. pallidum and C. trachomatis. The extent of strand bias, however, cannot be explained on the basis of the GC-content of the genome, use of all-purine codons or an excess in the amino acids that are encoded by such codons. The probable causes and effects of this phenomenon are discussed.
 ...
PMID:Polypurine.polypyrimidine sequences in complete bacterial genomes: preference for polypurines in protein-coding regions. 1072 21

The in vitro antibacterial spectrum of gatifloxacin was compared with those of ciprofloxacin and ofloxacin. Gatifloxacin was two- to four-fold more potent than comparator quinolones against staphylococci, streptococci, pneumococci and enterococci (gatifloxacin MIC90s, < or =1 mg/L, except 4 mg/L against methicillin-resistant Staphylococcus aureus and Enterococcus faecium). Gatifloxacin was two-fold less potent than ciprofloxacin, and the same as or two-fold more potent than ofloxacin against Enterobacteriaceae (MIC90s, 0.06-0.5 mg/L against most members of the Enterobacteriaceae and < or =1 mg/L against Proteus/Morganella spp.). Relative to the comparator quinolones, gatifloxacin was two- to four-fold more potent against Providencia spp., and had good potency against Acinetobacter spp. (MIC90s, 0.25-1 mg/L). Gatifloxacin and ofloxacin had similar anti-pseudomonal potency, with corresponding MIC90s of 4, 8 and 0.25 mg/L for Pseudomonas aeruginosa, Pseudomonas fluorescens and Pseudomonas stutzeri, while ciprofloxacin had two- to eight-fold more potency. The three quinolones were equipotent against Burkholderia cepacia (MIC90s, 8 mg/L), but gatifloxacin was two-fold more potent against Stenotrophomonas maltophilia (MIC90, 4 mg/L). Gatifloxacin was highly potent (MIC90s, 0.03-0.06 mg/L) against Haemophilus influenzae, Legionella spp., Helicobacter pylori and had at least eight-fold better anti-chlamydial and anti-mycoplasma potency (gatifloxacin MIC90s, 0.13 mg/L). The higher quinolone MICs for ureaplasma (MIC90s, 4-8 mg/L) may be due to the acidic pH of the ureaplasma test medium, which antagonizes quinolones. Like other quinolones, gatifloxacin had poor potency against Mycobacterium avium-intracellulare, though it was eight- to 16-fold more potent against Mycobacterium tuberculosis (MIC90, 0.25 mg/L). Of the three quinolones, only gatifloxacin had activity against Bacteroides fragilis and Clostridium difficile. In summary, gatifloxacin is a broad-spectrum 8-methoxy fluoroquinolone that is more potent than ciprofloxacin and ofloxacin against Gram-positive bacteria, chlamydia, mycoplasma, mycobacteria and anaerobes.
 ...
PMID:In vitro antibacterial spectrum of a new broad-spectrum 8-methoxy fluoroquinolone, gatifloxacin. 1074 19

There are two major categories of drug-resistant bacteria that can cause severe and intractable infections. The first includes multi drug-resistant Mycobacterium tuberculosis(MDRMT), penicillin-resistant Streptococcus pneumoniae(PRSP), and beta-lactamase positive or negative ampicillin-resistant Haemophilus influenzae, which used to be isolated from the patients with community-acquired infection. However, these pathogens have been often isolated in recent years from patients with hospital/chronic care facilities/nursing-home mass infection. The second major category includes methicillin-resistant Staphylococcus aureus(MRSA), vancomycin-resistant Enterococcus species(VRE), Pseudomonas aeruginosa, and Enterobacteriaceae including extended-spectrum beta-lactamases(ESBLs) producing strain, which are mainly isolated from compromised patients with nosocomial infections. The pathogenicity of these pathogens, almost all of which are found in the normal flora of humans, is weak, but often cause nosocomial infections in compromised patients. We need, therefore, surveillance system for these pathogens, and carefully determine whether these pathogens, if isolated, are causative pathogens.
 ...
PMID:[Drug-resistant bacteria in clinical situations]. 1080 87


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>