English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Background   Mycoplasma pneumoniae  has previously been characterized as a micro-organism that is genetically highly stable. In spite of this genetic stability, homologous DNA recombination has been hypothesized to lie at the basis of antigenic variation of the major surface protein, P1, of  M. pneumoniae . In order to identify the proteins that may be involved in homologous DNA recombination in  M. pneumoniae , we set out to characterize the MPN229 open reading frame (ORF), which bears sequence similarity to the gene encoding the single-stranded DNA-binding (SSB) protein of other micro-organisms.    Results  The MPN229 ORF has the capacity to encode a 166-amino acid protein with a calculated molecular mass of 18.4 kDa. The amino acid sequence of this protein ( Mpn  SSB) is most closely related to that of the protein predicted to be encoded by the MG091 gene from  Mycoplasma genitalium  (61% identity). The MPN229 ORF was cloned, and different versions of  Mpn  SSB were expressed in  E. coli  and purified to > 95% homogeneity. The purified protein was found to exist primarily as a homo-tetramer in solution, and to strongly and selectively bind single-stranded DNA (ssDNA) in a divalent cation- and DNA substrate sequence-independent manner.  Mpn  SSB was found to bind with a higher affinity to ssDNA substrates larger than 20 nucleotides than to smaller substrates. In addition, the protein strongly stimulated  E. coli  Recombinase A (RecA)-promoted DNA strand exchange, which indicated that  Mpn  SSB may play an important role in DNA recombination processes in  M. pneumoniae .    Conclusion  The  M. pneumoniae  MPN229 gene encodes a protein,  Mpn  SSB, which selectively and efficiently binds ssDNA, and stimulates  E. coli  RecA-promoted homologous DNA recombination. Consequently, the  Mpn  SSB protein may play a crucial role in DNA recombinatorial pathways in  M. pneumoniae . The results from this study will pave the way for unraveling these pathways and assess their role in antigenic variation of  M. pneumoniae .

bmc microbiology

The Mycoplasma pneumoniae MPN229 gene encodes a protein that selectively binds single-stranded DNA and stimulates Recombinase A-mediated DNA strand exchange