The mechanisms underlying antigenic variation and maintenance of genomic integrity in Mycoplasma pneumoniae and Mycoplasma genitalium

ABSTRACT The P1, P40, and P90 proteins of Mycoplasma pneumoniae and the MgPa and P110 proteins of Mycoplasma genitalium are immunogenic adhesion proteins that display sequence variation. Consequently, these proteins are thought to play eminent roles in immune evasive strategies. For each of the five proteins, a similar underlying molecular mechanism for sequence variation was hypothesized, i.e., modification of the DNA sequences of their respective genes. This modification is thought to result from homologous recombination of parts of these genes with repeat elements (RepMp and MgPar elements in M. pneumoniae and M. genitalium, respectively) that are dispersed throughout the bacterial genome. Proteins that are potentially involved in homologous DNA recombination have been suggested to be implicated in recombination between these repeat elements and thereby in antigenic variation. To investigate this notion, we set out to study the function of the RecA homologs that are encoded by the M. pneumoniae MPN490 and M. genitalium MG339 genes. Both proteins, which are 79% identical on the amino acid level, were found to promote recombination between homologous DNA substrates in an ATP-dependent fashion. The recombinational activities of both proteins were Mg2+ and pH dependent and were strongly supported by the presence of single-stranded DNA binding protein, either from M. pneumoniae or from Escherichia coli. We conclude that the MPN490- and MG339-encoded proteins are RecA homologs that have the capacity to recombine homologous DNA substrates. Thus, they may play a central role in recombination between repetitive elements in both M. pneumoniae and M. genitalium.

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Characterization of MGC2, a Mycoplasma gallisepticum Cytadhesin with Homology to the Mycoplasma pneumoniae 30-Kilodalton Protein P30 and Mycoplasma genitalium P32

Infection and Immunity ◽

10.1128/iai.66.7.3436-3442.1998 ◽

1998 ◽

Vol 66 (7) ◽

pp. 3436-3442 ◽

Cited By ~ 41

Author(s):

Linda L. Hnatow ◽

Calvin L. Keeler ◽

Laura L. Tessmer ◽

Kirk Czymmek ◽

John E. Dohms

Keyword(s):

Mycoplasma Pneumoniae ◽

Reverse Transcription ◽

Mycoplasma Genitalium ◽

Mycoplasma Gallisepticum ◽

Immunogold Labeling ◽

Respiratory Pathogen ◽

Functional Studies ◽

Reverse Transcription Pcr ◽

Attachment Inhibition

ABSTRACT A second cytadhesin-like protein, MGC2, was identified in the avian respiratory pathogen Mycoplasma gallisepticum. The 912-nucleotide mgc2 gene encodes a 32.6-kDa protein with 40.9 and 31.4% identity with the M. pneumoniae P30 andM. genitalium P32 cytadhesins, respectively. Functional studies with reverse transcription-PCR, immunoblotting, double-sided immunogold labeling, and attachment inhibition assays demonstrated homology to the human mycoplasmal P30 and P32 cytadhesins. These findings suggest that there is a family of cytadhesin genes conserved among pathogenic mycoplasmas infecting widely divergent hosts.

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Identification of a ribonuclease H gene in both Mycoplasma genitalium and Mycoplasma pneumoniae by a new method for exhaustive identification of ORFs in the complete genome sequences

FEBS Letters ◽

10.1016/s0014-5793(99)00075-7 ◽

1999 ◽

Vol 445 (1) ◽

pp. 6-8 ◽

Cited By ~ 9

Author(s):

Matthew I Bellgard ◽

Takashi Gojobori

Keyword(s):

Mycoplasma Pneumoniae ◽

Complete Genome ◽

Mycoplasma Genitalium ◽

New Method ◽

Ribonuclease H ◽

Genome Sequences ◽

H Gene

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Uncoupling of the apyrimidinic/apurinic endonucleolytic and 3′→5′ exonucleolytic activities of the Nfo protein of Mycoplasma pneumoniae through mutation of specific amino acid residues

Microbiology ◽

10.1099/mic.0.077578-0 ◽

2014 ◽

Vol 160 (6) ◽

pp. 1087-1100 ◽

Cited By ~ 3

Author(s):

Silvia Estevão ◽

Pieternella E. van der Spek ◽

Annemarie M. C. van Rossum ◽

Cornelis Vink

Keyword(s):

Mycoplasma Pneumoniae ◽

Divalent Cations ◽

Single Point ◽

Dna Recombination ◽

Point Mutations ◽

Mycoplasma Genitalium ◽

Amino Acid Residues ◽

Specific Amino Acid ◽

Cleavage Activity ◽

Ap Sites

The DNA recombination and repair machineries of Mycoplasma pneumoniae and Mycoplasma genitalium were predicted to consist of a set of ~11 proteins. The function of one of these proteins was inferred from its homology with proteins belonging to the Endo IV enzyme family. The members of this family function in the repair of apyrimidinic/apurinic (AP) sites in DNA. As such activity may be crucial in the mycoplasmal life cycle, we set out to study the Endo IV-like proteins encoded by M. pneumoniae and M. genitalium. Both proteins, termed Nfo Mpn and Nfo Mge , respectively, were assessed for their ability to interact with damaged and undamaged DNA. In the absence of divalent cations, both proteins exhibited specific cleavage of AP sites. Surprisingly, the proteins also recognized and cleaved cholesteryl-bound deoxyribose moieties in DNA, showing that these Nfo proteins may also function in repair of large DNA adducts. In the presence of Mg2+, Nfo Mpn and Nfo Mge also showed 3′→5′ exonucleolytic activity. By introduction of 13 single point mutations at highly conserved positions within Nfo Mpn , two major types of mutants could be distinguished: (i) mutants that showed no, or limited, AP cleavage activity in the presence of EDTA, but displayed significant levels of AP cleavage activity in the presence of Mg2+; these mutants displayed no, or very low, exonucleolytic activity; and (ii) mutants that only demonstrated marginal levels of AP site cleavage activity in the presence of Mg2+ and did not show exonucleolytic activity. Together, these results indicated that the AP endonucleolytic activity of the Nfo Mpn protein can be uncoupled from its 3′→5′ exonucleolytic activity.

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In Vitro Activities of Eravacycline and Other Antimicrobial Agents against Human Mycoplasmas and Ureaplasmas

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00698-20 ◽

2020 ◽

Vol 64 (8) ◽

Author(s):

Ken B. Waites ◽

Donna M. Crabb ◽

Li Xiao ◽

Lynn B. Duffy ◽

Sixto M. Leal

Keyword(s):

Mycoplasma Pneumoniae ◽

Antimicrobial Agents ◽

Susceptibility Testing ◽

Ureaplasma Urealyticum ◽

Mycoplasma Hominis ◽

Mycoplasma Genitalium ◽

Content Type ◽

Ureaplasma Parvum

ABSTRACT We performed in vitro susceptibility testing for eravacycline in comparison to 4 other antimicrobials against 10 Mycoplasma genitalium, 40 Mycoplasma hominis, 44 Mycoplasma pneumoniae, 20 Ureaplasma parvum, and 20 Ureaplasma urealyticum isolates. All eravacycline MICs were ≤0.25 μg/ml, except that for one isolate of M. genitalium, for which the MIC was 2 μg/ml. Eravacycline was markedly more potent than tetracycline, azithromycin, moxifloxacin, and clindamycin against all isolates tested, which included 37 macrolide, tetracycline, and/or fluoroquinolone-resistant organisms.

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Common Deoxyribonucleic Acid Sequences in Mycoplasma genitalium and Mycoplasma pneumoniae Genomes

International Journal of Systematic Bacteriology ◽

10.1099/00207713-36-3-426 ◽

1986 ◽

Vol 36 (3) ◽

pp. 426-430 ◽

Cited By ~ 23

Author(s):

D. YOGEV ◽

S. RAZIN

Keyword(s):

Mycoplasma Pneumoniae ◽

Deoxyribonucleic Acid ◽

Mycoplasma Genitalium

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Comparative In Vitro Susceptibilities of Human Mycoplasmas and Ureaplasmas to a New Investigational Ketolide, CEM-101

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00090-09 ◽

2009 ◽

Vol 53 (5) ◽

pp. 2139-2141 ◽

Cited By ~ 54

Author(s):

Ken B. Waites ◽

D. M. Crabb ◽

Lynn B. Duffy

Keyword(s):

Mycoplasma Pneumoniae ◽

Mycoplasma Hominis ◽

Mycoplasma Genitalium ◽

Mycoplasma Fermentans

ABSTRACT MICs were determined for an investigational ketolide, CEM-101, and azithromycin, telithromycin, doxycycline, levofloxacin, clindamycin, and linezolid against 36 Mycoplasma pneumoniae, 5 Mycoplasma genitalium, 13 Mycoplasma hominis, 15 Mycoplasma fermentans, and 20 Ureaplasma isolates. All isolates, including two macrolide-resistant M. pneumoniae isolates, were inhibited by CEM-101 at ≤0.5 μg/ml, making CEM-101 the most potent compound tested.

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