Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A polymerase chain reaction assay was developed for the specific detection of Mycoplasma iowae, a poultry pathogen. Two primers were chosen in the DNA region located immediately 5' of the ribosomal genes operon. Under our PCR conditions, specific amplification of all M. iowae strains tested was achieved, and none of 17 other Mycoplasma species isolated from birds gave an amplification product. We obtained amplification from culture medium samples of M. iowae by using Tth DNA polymerase instead of Taq DNA polymerase, and we were able to detect as few as 10 organisms. Finally, we described a dot blot hybridization test, using cold labelling and chemiluminescence, which is very convenient for routine detection of M. iowae.
Mol Cell Probes 1996 Feb
PMID:Specific detection of Mycoplasma iowae using polymerase chain reaction. 868 73

A polymerase-chain-reaction-based detection system for Mycoplasma fermentans was established. The highly conserved tuf gene, which encodes elongation factor Tu of prokaryotes, served as target sequence for the PCR. With two PCR oligodeoxynucleotides, which were selected from M. fermentans specific sequences of the tuf gene, we amplified a 850 base pair DNA fragment. Via the biotin-moiety of one primer the PCR fragments were immobilized on streptavidin-coated microtitre plates. After alkaline denaturation a digoxigenin-labelled M. fermentans specific DNA probe was hybridized to the single stranded immobilized PCR fragment. Detection was performed by addition of an alkaline phosphatase conjugated anti-digoxigenin antibody. 4-methyl-umbelliferyl-phosphate was used as a fluorogenic substrate. Amplification of 10 fg chromosomal target DNA was detected by this 'DNA enzyme immuno assay (DEIA)' technique, corresponding to seven genome copies. Our study supports the presumption that the tuf gene proves to be a suitable target sequence for the PCR based detection of any bacterial species. Furthermore, hybridization of PCR fragments with radio-labelled DNA probes should no longer be necessary, because a very sensitive non-radioactive test system can easily be established with the 'DEIA' technique.
Mol Cell Probes 1996 Feb
PMID:Development of an amplification and hybridization assay for the specific and sensitive detection of Mycoplasma fermentans DNA. 868 79

Wall-less prokaryotes in the genus Mycoplasma include over 90 species of infectious agents whose pathogenicity for humans and other animals is currently being assessed. Molecular characterization of surface proteins is critical in this regard but is hampered by the lack of genetic systems in these organisms. We used TnphoA transposition to systematically mutagenize, in Escherichia coli, a genomic plasmid library constructed from Mycoplasma fermentans, a potential human pathogen. The strategy circumvented problems of expressing mycoplasma genes containing UGA (Trp) codons and relied on the construction of the vector pG7ZCW, designed to reduce TnphoA transposition into vector sequences. Functional phoA gene fusions directly identified genes encoding 19 putative membrane-associated proteins of M. fermentans. Sequences of fusion constructs defined three types of export sequence: (1) non-cleavable, membrane-spanning sequences, (2) signal peptides with signal peptidase (SPase) I-like cleavage sites, and (3) signal peptides with SPase II-like lipoprotein-cleavage sites which, like most other mycoplasmal lipoprotein signals analysed to date, differed from those in several Gram-negative and Gram-positive eubacteria in their lack of a Leu residue at the -3 position. Antibodies to synthetic peptides that were deduced from two fusions to predicted lipoproteins, identified corresponding amphiphilic membrane proteins of 57 kDa and 78 kDa expressed in the mycoplasma. The P57 sequence contained a proline-rich N-terminal region analogous to an adhesin of Mycoplasma gallisepticum. The P78 protein was identical to a serologically defined phase-variant surface lipoprotein. TnphoA mutagenesis provides an efficient means of systematically characterizing functionally diverse lipoproteins and other exported proteins in mycoplasmas.
Mol Microbiol 1995 Oct
PMID:Identification of mycoplasma membrane proteins by systematic Tn phoA mutagenesis of a recombinant library. 870 47

Mycoplasma pneumoniae is the leading cause of pneumonia in older children and young adults. Mycoplasma adherence to the respiratory epithelium (cytadherence) is required for colonization and pathogenesis. Although considered to be among the smallest and simplest known prokaryotes, this cell-wall-less bacterium possesses a highly differentiated terminal structure that is thought to be functional in mycoplasma cell division, gliding motility, and cytadherence. Mutant analysis has identified mycoplasma proteins associated with cytadherence, and revealed novel regulatory features. Ultrastructural and biochemical studies have established the subcellular location and interaction of key components, several of which are phosphorylated by ATP-dependent kinase(s) in a manner that is responsive to changing nutritional conditions. This review summarizes recent progress in defining the composition, organization and regulation of the attachment organelle. What emerges is a picture of M. pneumoniae cytadherence as a multifactorial process that extends well beyond adhesin-receptor recognition.
Mol Microbiol 1996 Apr
PMID:Mycoplasma pneumoniae cytadherence: unravelling the tie that binds. 873 24

A polymerase chain reaction (PCR)-based assay was developed for the detection of Mycoplasma hominis. This assay generates a 152-bp PCR product which was part of an initial 471-bp M. hominis genomic DNA fragment. The 471-bp DNA fragment was shown by hybridization analysis to be unique for M. hominis. The PCR assay can amplify as few as 18 molecules of target DNA. This diagnostic assay offers potential for wide clinical application as it is rapid and can be successfully performed on crude sample preparations from a variety of media or biopsies. The use of this assay should aid in defining the aetiologic and pathologic roles played by M. hominis and thereby benefit patients.
Mol Cell Probes 1995 Dec
PMID:Development of a diagnostic polymerase chain reaction assay for detection of Mycoplasma hominis. 880 12

Mycoplasma hyorhinis contains clustered vlp genes encoding variable lipoproteins (Vlps), the major coat proteins and surface antigens of this wall-less prokaryotic pathogen. vlp genes are subject to discrete, high frequency mutations independently affecting the size or the expression of variant Vlp products. Change in Vlp size occurs by mutations altering the number of tandem intragenic repeats at the 3' end of each single-copy vlp gene. In this report, phase-variant Vlp expression is shown to result from altered vlp gene transcription. vlpA, vlpB and vlpC transcripts were monitored in a clonal lineage selected to display various Vlp phenotypes. Each vlp gene was expressed as a distinct transcript, which was subject to drastic ON/OFF switches associated with random insertion/ deletion mutations in a homopolymeric tract of adenine residues in the promoter region of all vlp genes. Unexpectedly, the level of vlp transcripts appeared to depend on the length of the corresponding genes in the ON configuration. Higher proportional levels of shorter vlp transcripts were shown to reflect a greater abundance of short Vlp lipoproteins present in L-[35S]-cysteine-labelled membrane protein preparations. The vlp cluster provides a heritable, and highly mutable, locus for the generation of surface diversity through random promoter mutations affecting the expression of genes, whose products also vary in length and abundance, by virtue of separate mutations in structural regions of the genes.
Mol Microbiol 1995 Nov
PMID:Mycoplasma hyorhinis vlp gene transcription: critical role in phase variation and expression of surface lipoproteins. 881 88

The chromosome of the murine pathogen Mycoplasma pulmonis undergoes rearrangements at a high frequency. We show that some of these rearrangements regulate the phase-variable expression of a cluster of genes (the vsa locus) that encode the variable V-1 surface antigens. Only one vsa gene is associated with an expression site; the other vsa genes are transcriptionally silent. The silent genes lack the 5' end region (promoter and ribosome-binding site) that is present in the expressed gene, and DNA rearrangements regulate gene expression by reassorting the 5' end region from an expressed gene with the 3' end region from a previously silent gene. All vsa rearrangements identified so far are site-specific DNA inversions that occur between copies of a specific 34 bp sequence that is conserved in each vsa gene. Interestingly, DNA inversions within the vsa locus apparently occur in concert with inversion of the hsd1 element, which regulates restriction and modification activity in M. pulmonis.
Mol Microbiol 1995 Nov
PMID:Mechanism of antigenic variation in Mycoplasma pulmonis: interwoven, site-specific DNA inversions. 881 92

Mycoplasma pneumoniae is a major cause of tracheobronchitis and pneumonia in older children and young adults. The lack of adequate tools for genetic analysis has hindered the elucidation of function and regulation of mycoplasma virulence determinants. We describe here the use of a transposon vector to deliver the cloned gene for the cytadherence-associated protein HMW1 in M. pneumoniae. A 4.95 kbp BamHI fragment encoding all but the C-terminal end of HMW1 was cloned into a modified Tn4001 and transformed into wild-type M. pneumoniae and into a non-cytadhering mutant lacking HMW1-HMW5. Southern blot hybridizations confirmed insertion of the transposon and the presence of both the resident and recombinant hmw1 alleles. Analysis by Western immunoblotting revealed a truncated HMW1 (HMW1') in the transformants, the level of HMW1' being dependent upon the orientation of the hmw1 gene in the transposon and the site of insertion. Similar expression patterns were noted in wild-type and mutant backgrounds. However, expression of wild-type levels of HMW1' in the mutant did not restore adherence. Finally, HMW4 and HMW1 were shown to be products of the same gene, HMW4 being a heat-modified derivative of HMW1.
Mol Microbiol 1996 Mar
PMID:Expression in Mycoplasma pneumoniae of the recombinant gene encoding the cytadherence-associated protein HMW1 and identification of HMW4 as a product. 883 Feb 65

There are at least six small stable RNAs in Mycoplasma capricolum cells besides tRNAs and rRNAs. One of them, MCS5 RNA, is a homolog of RNase P RNA. The predicted secondary structure of this RNA is essentially the same as that of other eubacterial RNase P RNAs. MCS5 RNA is more similar to the RNase P RNA of B. Subtilis than to that of E. coli. This is consistent with previous conclusions that mycoplasmas are phylogenetically related to the low G + C Gram-positive bacterial group. The major substrates for MCS5 RNA must be the precursors of tRNAs. The precursor of MCS6 RNA, which is a homolog of the E. coli 10Sa RNA, may also be a substrate for the MCS5 RNA because this RNA has a tRNA-like structure at its 5' and 3' ends.
Mol Biol Rep
PMID:RNase P RNA of Mycoplasma capricolum. 890 98

Nucleic acid sequence-based amplification, NASBA, is an isothermal amplification technique for nucleic acids and was used for typing a collection of 24 Mycoplasma pneumoniae strains. A set of primers was chosen from the 16S rRNA sequence alignment of Mycoplasma species. The nucleotide sequences of the (-)RNA amplicons were determined for M. pneumoniae strains M15/83 (type 1) and FH (type 2), and revealed a one-point difference at the 16S rRNA level between the two types. Based on this result, two type-specific probes were constructed. The probes were hybridized in solution with the amplified nucleic acids of 24 M. pneumoniae strains in an enzyme-linked gel assay (ELGA). The results obtained by NASBA-based typing are in agreement with the classification of the 24 M. pneumoniae strains into two types by other typing methods, confirming the reliability of this technique.
Mol Cell Probes 1996 Oct
PMID:Typing of Mycoplasma pneumoniae by nucleic acid sequence-based amplification, NASBA. 891 Aug 85


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