Genome of Mycoplasma arthritidis

Abstract

The genomes of several species of mycoplasma have been sequenced. Most of these species rely on the glycolytic pathway for energy production, with the one exception of Ureaplasma, a species that breaks down urea as its principle source of acquiring energy. Several species, including as Mycoplasma arthritidis, are nonglycolytic and can use arginine as their source of energy. Described here are the genome sequence and a transposon library of M. arthritidis. The genome of 820,453 bp is typical in size for a mycoplasma and contains two large families of genes that are predicted to code for phase-variable proteins. The transposon library was constructed using a minitransposon that inserts stably into the mycoplasma genome. Of the 635 predicted coding regions, 218 were disrupted in a library of 1,100 members. Dispensable genes included the gene coding for the MAM superantigen and genes coding for ribosomal proteins S15, S18, and L15.Mycoplasma arthritidis is a natural pathogen of rats, causing severe polyarthritis. Arthritis in mice can be experimentally induced by injection of M. arthritidis into the tail vein. Disease in mice is more chronic than in rats, with lesions similar to those seen in human rheumatoid arthritis (25). Factors thought to contribute to the virulence of M. arthritidis are MAM, a potent superantigen secreted by the mycoplasma, and the M. arthritidis adhesins (MAAs) that have a role in cytadherence (32).The genome sequences of several species of mycoplasma are known (see http://cbi.labri.fr/outils/molligen/). Other than Ureaplasma, which utilizes the hydrolysis of urea to generate ATP, all of the mycoplasma species that have sequenced genomes are glycolytic. Some species of mycoplasma such as M. arthritidis are nonglycolytic, and thus it was anticipated that the sequence of the M. arthritidis genome would reveal new aspects of mycoplasma physiology. Nonglycolytic mycoplasmas generally catabolize arginine as a major source of energy, and, indeed, the required genes for arginine catabolism were identified in the genome sequence of M. arthritidis.Described here is the genome sequence of the virulent M. arthritidis strain 158L3-1 (3, 31). Strain 158L3-1 is a lysogen containing the 16-kb genome of the MAV1 bacteriophage. No additional prophages were noted in the genome. The sequence revealed features offering insight into the mechanisms by which the mycoplasma causes chronic inflammation, including two families of genes that are predicted to code for phasevariable proteins and a predicted gene product related to but distinct from MAM.We also describe a transposon library of M. arthritidis strain 158, the nonlysogenic parent of 158L3-1. The library was created using minitransposons derived from Tn4001 that inserts into the genome at essentially random sites. The genomic location of the minitransposon was determined for 1,113 library members. Using criteria for gene inactivation previously developed for transposon mutagenesis of Mycoplasma pulmonis, 218 of the predicted protein coding regions, including ...

Dietary nitrogen alters codon bias and genome composition in parasitic microorganisms

“…These comprised four plant glycolytic parasite species ( Candidatus Phytoplasma asteris [53], Candidatus Phytoplasma austrailense [54], Candidatus Phytoplasma mali [55], Candidatus Phytoplasma solani [56], Candidatus Phytoplasma strawberry [57]), five animal glycolytic parasite species ( Mycoplasma conjunctivae [58], Mycoplasma genitalium [59], Mycoplasma haemocanis [60], Mycoplasma hyopneumoniae [61], Mycoplasma parvum [62]) and seven parasite species known to obtain energy from catabolism of amino acids or amino sugars ( Mycoplasma arthritidis [63], Mycoplasma capricolum [PRJNA16208], Mycoplasma fermentans [64], Mycoplasma hominis [23], Mycoplasma penetrans [65], Mycoplasma putrefaciens [66], Mycoplasma synoviae [67]). A further four parasite species were used for testing the predictive capacity of the model for synonymous codon use ( Mycoplasma crocodyli [68], Mycoplasma hyorhinis [69], Mycoplasma leachii [70], Mycoplasma mycoides [70]).…”

Critical Role of Dispensable Genes inMycoplasma agalactiaeInteraction with Mammalian Cells

“…Similar approaches have been developed with a few mycoplasma species, mainly with the aim of defining the minimal set of essential genes required to sustain autonomous life under axenic conditions (12,15,18,25). However, the genetic information necessary to develop interactions of mycoplasma with its animal host is likely to differ from the minimal set of essential genes required for laboratory growth.…”

Genome Sequences of Mycoplasma alligatoris A21JP2 T and Mycoplasma crocodyli MP145 T

“…MUMer alignments found only limited synteny between the two species. Site-specific gene knockout methods were ineffective in M. alligatoris, but a library of M. alligatoris knockout mutants was created by random transposon insertion using the mini-Tn4001tetM plasmid pTF20 (4). Unique stable knockouts were obtained for ϳ1,100 random Tet r clones mapped using direct genomic DNA sequencing via extension from primers complementary to the transposon.…”