PCR技术在三种男性性病检测中的应用

本文用聚合酶链反应ＰＣＲ技术对３６９例男性泌尿生殖道炎患者进行淋球菌（ＮＧ）,解脲支原体（ＭＰＵ）和沙眼衣原体（ＣＴ）的检测,阳性率分别为３５．５％,３０．５％和１１．６％,同时,我们对高度怀疑为淋病患者７４例及６３例非淋病性尿道炎患者进行细菌培养和ＰＣＲ的同时检测,淋病患者细菌培养阳性检测率为３１．１％,与９２-９４年间所进行的培养检测结果基本一致,均低于ＰＣＲ检测结果（７７．１％）,解脲支原体培养阳性率为１７．５％,亦明显低于ＰＣＲ结果（３０．５％）,此外,对同一患者进行ＮＧ＋ＭＰＵ和ＭＰＵ＋ＣＴＰＣＲ检测,发现约４０％的淋病患者并发ＭＰＵ感染,而ＭＰＵ和ＣＴ复合感染亦在１０％左右。上述结果说明ＰＣＲ方法在性病病原体的诊断中比细菌培养法更为可靠,特别是在多种病原体复合感染情况下更为有效。     

The phylogeny of Mycoplasma bovis as determined by sequence analysis of the 16S rRNA gene

Abstract The nucleotide sequence of the 16S rRNA gene of Mycoplasma bovis has been determined. Comparisons with other 16S rRNA sequences of mycoplasmas showed that Mycoplasma agalactiae is phylogenetically the closet relative. In total, only eight nucleotides differed between the M. bovis and M. agalactiae 16S rRNA sequences. The phylogenetic position of M. bovis with respect to other mycoplasmas was determined by sequence comparisons and from features in the secondary structure of 16S rRNA.     

Alternatives to arginine as energy sources for the non-fermentative Mycoplasma gallinarum

Abstract In contrast to previously studied non-fermentative arginine-hydrolysing (F-/A+) Mycoplasma species, M. gallinarum cells suspended in salts solution oxidised ethanol and L-lactic, pyruvic and 2-oxobutyric acids. The organic acids were additionally shown effectively to replace arginine as energy sources in growth media. However, their presence did not inhibit arginine hydrolysis, nor did arginine inhibit organic acid catabolism. The ability to oxidase organic acids is a potentially useful diagnostic character enabling sub-division of the F-/A+ Mycoplasma species. M. gallinarum also differed from previously studied F-/A+ mycoplasmas in possessing relatively high NADH oxidase activity and producing H₂O₂ as only a minor product of NADH oxidation.     

Sequence polymorphisms within the pMGA genes and pMGA antigenic variants in Mycoplasma gallisepticum

Antigenic variants of Mycoplasma gallisepticum major surface lipoprotein, pMGA, are encoded by a large gene family. In this study sequence analyses of the PCR-amplified pMGA genes showed two types of sequences similar to the pMGA1.2 gene in M. gallisepticum strains. They differed in the sequence encoding a proline-rich region (PRR) at the N-terminus of the pMGA protein. The type A genes had sequences similar to the published pMGA1.2 gene sequence of strain S6, whereas the type B genes lacked the second repetitive segment encoding PTPN sequence within PRR and were similar to the published sequence of PG31 strain. Low in vitro passages of M. gallisepticum strains isolated recently in Slovenia from four avian species showed very different expression patterns of pMGA1.2 and pMGA1.9 genes. Among isogenic populations of S6(B) and IHB1 strains a high frequency of pMGA antigenic variants lacking an epitope for monoclonal antibody (mAb) 71 was found. Strain IHB1 clones, which synthesized pMGA recognized by mAb 71, transcribed pMGA genes whose partial sequence encoded the amino acid sequence (262)TNGDEPRSVS of the mAb 71 epitope. Other IHB1 clones synthesized pMGA variants with different isoelectric points, lacking the epitope for mAb 71, but expressing downstream epitopes for other mAbs. Our study suggests that a molecular basis for pMGA antigenic variation lies in the corresponding changes at the DNA level.     

Kinetics and distribution of alcohol oxidising activity in Acholeplasma and Mycoplasma species

Alcohol metabolism by Acholeplasma and Mycoplasma cell suspensions was determined using changes in dissolved oxygen tension to monitor oxygen uptake. All seven Acholeplasma test species oxidised ethanol and (where tested) propanol, butanol and pentanol. The rate of oxidation, at any particular substrate concentration, decreased with increasing alcohol molecular mass. Amongst 20 Mycoplasma species tested, M. agalactiae, M. bovis, M. dispar, M. gallisepticum, M. pneumoniae and M. ovipneumoniae oxidised ethanol. Propanol was also oxidised by M. dispar and isopropanol by M. agalactiae, M. bovis and M. ovipneumoniae. Isopropanol was oxidised at particularly high rates (V(max)100 nmol O(2) taken up min(-1) mg cell protein(-1)) and with a relatively high affinity (K(m) value<2 mM); oxygen uptake was consistent with oxidation to acetone. The significance of alcohol oxidation is unclear, as it would not be predicted to lead to ATP synthesis.     

Infection of human B lymphoma cells by Mycoplasma fermentans induces interaction of its elongation factor with the intracytoplasmic domain of Epstein-Barr virus receptor (gp140, EBV/C3dR, CR2, CD21)

Human cell lines are often infected by mycoplama strains. We have demonstrated that when infected by Mycoplasma fermentans, human B lymphoma cell proliferation increased strongly. These infected B cells expressed a p45 kDa protein which interacted with the intracellular domain of CD21, the EBV/C3d receptor. p45 analysis demonstrated that this is a new gene which encodes an elongation factor originating from Mycoplasma fermentans. p45 interaction with CD21 was specific, there being no interaction with CD19. This is the first demonstration that Mycoplasma fermentans, in infecting human B cells, generates a p45 Mycoplasma component that interacts with CD21, which is involved in B cell proliferation.     

Re-suspension of T(1)44 vaccine cultures of Mycoplasma mycoides subsp mycoides SC in 1 molar MgSO(4) causes a drop in pH and a rapid reduction in titre

We report Mycoplasma bovis induces apoptotic death of bovine lymphocytes. Using flow cytometry analyzed propidium iodide inclusion we observed a loss in viable lymphocytes upon incubation of freshly isolated bovine PBMCs with M. bovis. The use of annexin V staining as well as TUNEL assays corroborated these findings. In addition, these assays indicated that the M. bovis induced lymphocyte death is apoptotic in nature. Subsequent experiments demonstrated that the prokaryotic protein production inhibitor chloramphenicol inhibited lymphocyte death induced by M. bovis, showing that M. bovis protein production is necessary for the induction of lymphocyte death, and that the death is not dependent upon the addition of apoptotic inducers as shown with other mycoplasmas. We also show that M. bovis is different from other bovine mycoplasmas (both pathogenic and non-pathogenic) with regards to this characteristic.     

Triclosan: a widely used biocide and its link to antibiotics

Mycoplasmas are cell wall-less bacteria at the low extreme in genome size in the known prokaryote world, and the minimal nature of their genomes is clearly reflected in their metabolic and regulatory austerity. Despite this apparent simplicity, certain species such as Mycoplasma pneumoniae possess a complex terminal organelle that functions in cytadherence, gliding motility, and cell division. The attachment organelle is a membrane-bound extension of the cell and is characterized by an electron-dense core that is part of the mycoplasma cytoskeleton, defined here for working purposes as the protein fraction that remains after extraction with the detergent Triton X-100. This review focuses on the architecture and assembly of the terminal organelle of M. pneumoniae. Characterizing the downstream consequences of defects involving attachment organelle components has made it possible to begin to elucidate the probable sequence of certain events in the biogenesis of this structure.     

Chemical analyses,local Shwartzman reactivity,and body weight-decreasing activity of aqueous-phenol extracts of Mycoplasma salivarium cells

Aqueous-phenol extracts of Mycoplasma salivarium ATCC 23064 cells (APM) showed demonstrable differences from lipopolysaccharides (LPSs) of Veillonella rodentium ATCC 17743. These were as follows: smaller amounts of amino sugars and an absence of 2-keto-3-deoxyoctonate; local Shwartzman reactivity and body weight-decreasing activity, even though the activities were rather weak compared with those of LPSs. Therefore, phenol-water extractive components of Mycoplasma salivarium might be of pathogenic importance in mediating damaging effects on the periodontium.