The nucleotide sequence of glycine tRNA from Mycoplasma mycoides sp. capri.

Using in vitro labelling techniques, a tRNAGly from M. mycoides sp. capri PG3 has been shown to have the sequence : pGCAGGUGs4UAGUUUAAUGGCAGAACUUC AGCCUUCCm6AAGCUGAUUGUGAGGGU psi CGAUUCCCUUCACCUGCUCCAOH. The anticodon is UCC and no other tRNAGly has been detected in the crude tRNA isolated from this organism. As is the case with some mitochondrial tRNAs, where the genome size of the organelle is small, it is possible that this tRNA is used to read all four glycine codons GGN.     

The nucleotide sequence of formylmethionine tRNA from Mycoplasma mycoides sp. capri.

The nucleotide sequence of Mycoplasma mycoides sp. capri PG3 formylmethionine tRNA has been determined, using in vitro labeling techniques, to be pC-G-C-G-G-G-G-s4U-A-G-A-G-C-A-G-U-D (U)-G-G-D-A-G-C-U-C-G-C-C-G-G-G-C-U-C-A-U-A-A-C-C-C-G-G-A-G-G-C-C-G-C-A-G-G-U-psi- C-G-A-G-U-C-C-U-G-C-C-C-C-C-G-C-A-A-C-C-AOH. This tRNA contains only three modified nucleosides s4U, D and psi, all of which are derived from uridine. Both in the structural features which distinguish eukaryotic from prokaryotic initiator RNAs and in the overall sequence, this tRNA resembles a typical prokaryotic initiator tRNA. A comparison of the sequence of this tRNA with those of other prokaryotic initiator tRNAs suggests that taxonomically the Mycoplasma may be less related to the Cyanophyta (Anacystis nidulans) than to the bacteria and less related to the Enterobacteriaceae (Escherichia coli) than to the Bacillaceae (Bacillus subtilis).     

丝状支原体山羊亚种PG3株的全基因组序列测定与分析

【目的】全面了解丝状支原体山羊亚种PG3株的全基因组序列信息,寻找该病原体的主要保护性抗原基因。【方法】利用高通量Illumina Hi Seq 2000测序技术对丝状支原体山羊亚种PG3株的全基因组进行测序与拼接,借助软件和数据库对全基因组序列所承载的遗传信息进行注释和分析。【结果】丝状支原体山羊亚种PG3株基因组大小为1 025 065 bp,G+C%为23.6%,预测含有846个编码基因。根据COG分类和KEGG代谢通路分类,基因组中绝大多数基因主要与蛋白翻译、核糖体结构与合成、DNA复制与修复、糖代谢和环境信号传递与转换方面有关。该菌株具有丝状支原体山羊亚种特有的麦芽糊精/麦芽糖代谢途径。与Mmc str.95010的基因组的比对结果显示二者具有良好的共线性关系。在基因组中发现3个串联排列的可变表面脂蛋白基因,即GL000459、GL000461和GL000462。【结论】获得丝状支原体山羊亚种PG3株的全基因组序列,分析基因组基本特征,初步解析3个串联排列的可变表面脂蛋白基因,为进一步研究支原体可变表面脂蛋白的功能和研制生物工程疫苗奠定基础。     

The nucleotide sequence of the 5S rRNA from Spiroplasma species BC3 and Mycoplasma mycoides sp. capri PG3

Using in vitro labelling techniques, the complete nucleotide sequence of the 5S ribosomal RNAs isolated from the honeybee pathogen, Spiroplasma species BC3 and Mycoplasma mycoides sp. capri PG3, have been determined. The latter shows only 3 differences from the reported sequence of M. capricolum 5S rRNA, indicating that these two species are very closely related. The Spiroplasma sequence is also 107 nucleotides long and a comparative analysis of the sequence confirms that this Spiroplasma species is closely related to the Mycoplasma species and that they and the Gram-positive eubacteria have descended from a common ancestor and in the process the cell wall-less organisms have lost a large percentage of their genome.     

The nucleotide sequence of the major glutamate transfer RNA from Schizosaccharomyces pombe.

The nucleotide sequence of glutamate tRNA1 from Schizosaccharomyces pombe was determined to be pU-C-C-G-U-U-G-U-m1G-G-U-C-C-A-A-C-G-G-C-D-A-G-G-A-U-U-C-G-U-C-G-C-U-U-U*-C-A-C-C-G-A-C-G-G-G-A-G-m5C-G-G-G-G-T-psi-C-G-A-C-U-C-C-C-C-G-C-A-A-C-G-G-A-G-C-C-AOH. The sequence differs markedly from that of S. cerevisiae tRNAGlu. S. pombe glutamate tRNA1 can be aminoacylated by the homologous glutaminyl-tRNA synthetase as well as by the corresponding enzyme from S. cerevisiae.     

Domain analysis of lipoprotein LppQ in Mycoplasma mycoides subsp. mycoides SC

The lipoprotein LppQ is the most prominent antigen of Mycoplasma mycoides subsp. mycoides small colony type (SC) during infection of cattle. This pathogen causes contagious bovine pleuropneumonia (CBPP), a devastating disease of considerable socio-economic importance in many countries worldwide. The dominant antigenicity and high specificity for M. mycoides subsp. mycoides SC of lipoprotein LppQ have been exploited for serological diagnosis and for epidemiological investigations of CBPP. Scanning electron microscopy and immunogold labelling were used to provide ultrastructural evidence that LppQ is located to the cell membrane at the outer surface of M. mycoides subsp. mycoides SC. The selectivity and specificity of this method were demonstrated through discriminating localization of extracellular (i.e., in the zone of contact with host cells) vs. integral membrane domains of LppQ. Thus, our findings support the suggestion that the accessible N-terminal domain of LppQ is surface exposed and such surface localization may be implicated in the pathogenesis of CBPP.     

Unconventional codon reading by Mycoplasma mycoides tRNAs as revealed by partial sequence analysis.

Continuing our investigation of the tRNA genes and gene products in Mycoplasma mycoides, we report the sequence of the gene for tRNALeu (CAA) as well as partial primary structures of the following tRNAs: Leu (CAA), Leu (UAG), Arg (UCU), Thr (AGU) and Ile (CAU). It is suggested that in M. mycoides, at least some of the family codon boxes are read by only one tRNA each, using an unconventional method which does not discriminate between the nucleotides in the third codon position. M. mycoides is the first free-living organism known to use an unconventional method of this kind.     

Isolation of a second cryptic plasmid from Mycoplasma mycoides subsp. mycoides

Plasmids have rarely been detected in organisms constituting the genus Mycoplasma. Recently, the isolation of a cryptic plasmid from Mycoplasma mycoides subsp. mycoides has been described, and we report here the isolation of a second cryptic plasmid from this species. Restriction map and Southern blot analyses show that the second plasmid is distinct from the previously described plasmid, although a limited region of homology was detected. The availability of mycoplasmal cryptic plasmids may lead to the development of cloning vectors that replicate in these organisms.     

ISMmy1, a novel insertion sequence of Mycoplasma mycoides subsp. mycoides small colony type

A new insertion sequence, ISMmy1, has been identified in the bovine pathogen Mycoplasma mycoides subsp. mycoides biotype small colony (MmymySC). The occurrence of ISMmy1 in 15 MmymySC strains and 12 other mycoplasmas was examined by Southern blotting. All MmymySC strains showed identical hybridisation patterns except for the type strain PG1(T), the vaccine strain T1Sr49, and the strain Afadé, which all had unique patterns. ISMmy1-like sequences were also found in the bovine pathogen Mycoplasma bovis strain Donetta(T) while mycoplasmas that are phylogenetically closer to MmymySC lack ISMmy1. This observation suggests horizontal transfer between MmymySC and M. bovis.     

Nucleotide sequence of Mycoplasma mycoides subspecies Mycoides plasmid pKMK1.

To facilitate the development of mycoplasmal cloning vectors, we have determined the nucleotide sequence of pKMK1, a cryptic plasmid isolated from Mycoplasma mycoides subsp. mycoides. It is 1875 bp in length and contains two open reading frames (ORFs) that share homology with ORFs from members of a large family of gram-positive bacterial plasmids which replicate via a single-stranded DNA intermediate. Putative origins of replication and candidate cloning sites have been identified.     

Cloning and nucleotide sequence analysis of a chloramphenicol acetyltransferase gene from Vibrio anguillarum.

The chloramphenicol resistant gene (cat) encoding chloramphenicol acetyltransferase (CAT) in a transferable R plasmid (pJA7324) isolated from the fish pathogen Vibrio anguillarum strain PT24 was cloned into the plasmid vector pUC19. The nucleotide sequence analysis of 1,348 base pair DNA identified an open reading frame encoding a protein of 216 amino acid residues with a calculated molecular mass of 25,471 daltons. The predicted amino acid sequences for this cat gene are 37-69% homologous with other CAT proteins of both Gram-negative and -positive bacteria. Colony hybridization performed with a PvuII-BamHI fragment including this cat gene as a probe, revealed that the same or similar chloramphenicol resistance genes existed among V. anguillarum isolates.     

Cloning and sequence analysis of the aminopeptidase My gene from Mycoplasma salivarium

Abstract The complete nucleotide sequence of a major component of aminopeptidase My purified from Mycoplasma salivarium was determined. The protein gene encoded a protein consisting of 520 amino acids with a molecular mass of 58079 Da. The protein contained two tryptophan residues, one of which was encoded by UGA. A computer-aided homology search suggested that aminopeptidase My had properties similar to those of leucine aminopeptidase (EC 3.4.11.1).     

The nucleotide sequence of spinach chloroplast tryptophan transfer RNA

Spinach chloroplast tRNATrp, purified by column chromatography and two-dimensional gel electrophoresis, has been sequenced using in vitro labeling techniques. The sequence is : pG-C-G-C-U-C-U-U-A-G-U-U-C-A-G-U-U-C-Gm-G-D-A-G-A-A-C-m2G-psi-G-G-G-psi-C-U-C-A-A*-A-A-C-C-C-G-A-U-G-N-C-G-U-A-G-G-T-psi-C-A-A-G-U-C-C-U-A-C-A-G-A-G-C-G-U-G -C-C-AOH. Like the E. coli suppressor tRNA psu+UGA which translates both the opal terminator codon U-G-A and the tryptophan codon U-G-G, spinach chloroplast tRNATrp has C-C-A as an anticodon and contains an A-U pair in the D-stem.     

The nucleotide sequence of 5S rRNA from Mycoplasma capricolum.

The nucleotide sequence of 5S rRNA from Mycoplasma capricolum is UUGGUGGUAUAGCAUAGAGGUCACACCUGUUCCCAUGCCGAACACAGAAGUUAAGCUCUAUUACGGUGAAGAUAUUACU GAUGUGAGAAAAUAGCAAGCUGCCAGUUOH. The length is 107 nucleotides long, and the shortest in all the 5S rRNAs so far known. The sequence is more similar to those of the gram-positive bacteria than those of the gram-negative bacteria.     

Cloning and nucleotide sequence of fosfomycin biosynthetic genes of Streptomyces wedmorensis

The biosynthetic pathway for production of the antibiotic fosfomycin by Streptomyces wedmorensis consists of four steps including the formation of a C-P bond and an epoxide. Fosfomycin production genes were cloned from genomic DNA using S. wedmorensis mutants blocked at different steps of the biosynthetic pathway. Four genes corresponding to each of the biosynthetic steps were found to be clustered in a DNA fragment of about 5 kb. Nucleotide sequencing of a large fragment revealed the presence of ten open reading frames, including the four biosynthetic genes and six genes with unknown functions.     

Studies of lactate dehydrogenase of Mycoplasma mycoides var. mycoides.

Polyacrylamide gel electrophoresis and isoelectric focusing techniques have been used to compare NAD-dependent L(plus) lactate dehydrogenases (LDH) from ten different strains of Mycoplasma mycoides var. mycoides. The enzymes were not distinguished from one another, or from normal bovine LDH 1 by these methods. The kinetic behaviour of LDH form M. mycoides (T1 vaccine strain) suggested that the enzyme could readily reduce pyruvate or oxidize lactate in a manner which, in vertebrates, requires two different isoenzymes.