mycoplasma pneumoniae large dna repetitive elements repmp1 show type specific organization among strains肺炎支原体大型dna重复元素repmp1显示类型菌株之间的特定组织.pdfVIP

Mycoplasma pneumoniae Large DNA Repetitive Elements RepMP1 Show Type Specific Organization among Strains Oxana Musatovova*, T. R. Kannan, Joel B. Baseman Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America Abstract Mycoplasma pneumoniae is the smallest self-replicating bacterium with a streamlined genome of 0.81 Mb. Complete genome analysis revealed the presence of multiple copies of four large repetitive elements (designated RepMP1, RepMP2/3, RepMP4 and RepMP5) that are implicated in creating sequence variations among individual strains. Recently, we described RepMP1-associated sequence variations between reference strain M129 and clinical isolate S1 that involved three RepMP1- genes (i.e. mpn130, mpn137 and mpn138). Using PCR and sequencing we analyze 28 additional M. pneumoniae strains and demonstrate the existence of S1-like sequence variants in nine strains and M129-like variants in the remaining nineteen strains. We propose a series of recombination steps that facilitates transition from M129- to S1-like sequence variants . Next we examined the remaining RepMP1-genes and observed no other rearrangements related to the repeat element. The only other detected difference was varying numbers of the 21-nucleotide tandem repeats within mpn127, mpn137, mpn501 and mpn524. Furthermore, typing of strains through analysis of large RepMPs localized within the adhesin P1 operon revealed that sequence divergence involving RepMP1-genes mpn130, mpn137 and mpn138 is strictly type-specific. Once more our analysis confirmed existence of two highly conserved groups of M. pneumoniae strains. Citation: Musatovova O, Kannan TR, Baseman JB (2012) Mycoplasma pneumoniae Large DNA Repetitive Elements RepMP1 Show Type Specific Organization among Strains. PLoS