title: Mutation of two Mycoplasma arthritidis surface lipoproteins with divergent functions in cytadherence.
abstract: Mycoplasma arthritidis is a natural pathogen of rats, causing an acute polyarthritis. Previous studies identified two membrane-bound lipoproteins, Maa1 and Maa2, thought to be associated with cytadherence of M. arthritidis strain 158p10p9. We have since confirmed that Maa1 is a major adhesin, although the role of Maa2 has proven more elusive. Both proteins were capable of eliciting protective immunity in rats against challenge with the virulent strain 158p10p9, suggesting that they may be important in pathogenesis. The purpose of this study was to better understand the roles of Maa1 and Maa2 in cytadherence in vitro. Insertion mutants were created for both genes by transposon mutagenesis. In vitro adherence of the Maa1 mutant KOMaa1 to rat L2 lung cells was reduced to the level previously reported for a spontaneous low-adherence mutant of 158p10p9 in which Maa1 is truncated and nonfunctional. Surprisingly, adherence of the Maa2 mutant KOMaa2 was approximately fivefold greater than that of the wild type. Complementation of KOMaa1 and KOMaa2 with wild-type alleles of maa1 and maa2, respectively, returned adherence to wild-type levels. This work confirms our earlier observation that Maa1 is a major adhesin for M. arthritidis strain 158p10p9. Maa2, on the other hand, may play a suppressive or modulatory role, possibly serving to release organisms from microcolonies at certain stages of infection.
authors.affiliation: Sanford School of Medicine, University of South Dakota, 414 E. Clark Street, Vermillion, South Dakota 57069, USA.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Bird
authors.forename: Kelly
authors.initials: K
authors.lastname: Graber
authors.forename: Allison
authors.initials: A
authors.lastname: Knutson
authors.forename: Leigh R
authors.initials: LR
authors.lastname: Washburn
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics* / Q000378:metabolism*; D000818:Animals; D001422:Bacterial Adhesion / Q000502:physiology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D015151:Immunoblotting; D008074:Lipoproteins / Q000502:physiology; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D016254:Mutagenesis, Insertional; D009154:Mutation; D045645:Mycoplasma arthritidis / Q000502:physiology*; D016133:Polymerase Chain Reaction; D051381:Rats
chemical_list: D018829:Adhesins, Bacterial; D001426:Bacterial Proteins; D008074:Lipoproteins; C112555:MAA2 protein, Mycoplasma arthritidis; D008565:Membrane Proteins
references.citation: Proc Soc Exp Biol Med. 1967 Jan;124(1):103-7
references.pmid: 6017752
references.citation: Plasmid. 2000 Sep;44(2):183-90
references.pmid: 10964628
references.citation: Arthritis Rheum. 1980 Jul;23(7):825-36
references.pmid: 6996688
references.citation: J Bacteriol. 1996 Oct;178(20):6078-81
references.pmid: 8830712
references.citation: Trends Microbiol. 2002 Aug;10(8):376-82
references.pmid: 12160636
references.citation: Infect Immun. 1995 Oct;63(10):4016-23
references.pmid: 7558313
references.citation: Infect Immun. 2001 Aug;69(8):5177-81
references.pmid: 11447202
references.citation: J Clin Microbiol. 1995 Sep;33(9):2271-9
references.pmid: 7494014
references.citation: Infect Immun. 1993 Jun;61(6):2670-80
references.pmid: 8500906
references.citation: Mol Biol Evol. 1987 May;4(3):203-21
references.pmid: 3328815
references.citation: Nucleic Acids Res. 1997 Sep 1;25(17):3389-402
references.pmid: 9254694
references.citation: Plasmid. 1999 Mar;41(2):120-4
references.pmid: 10087215
references.citation: J Bacteriol. 2000 Aug;182(15):4343-7
references.pmid: 10894746
references.citation: Infect Immun. 1998 Jun;66(6):2576-86
references.pmid: 9596719
references.citation: Infect Immun. 1973 May;7(5):691-9
references.pmid: 4587519
references.citation: Infect Immun. 1971 Oct;4(4):344-55
references.pmid: 5154887
references.citation: Infect Immun. 2003 Feb;71(2):671-5
references.pmid: 12540544
references.citation: Infect Immun. 2000 Feb;68(2):437-42
references.pmid: 10639401
references.citation: Gene. 1993 Dec 31;137(2):217-22
references.pmid: 8299950
references.citation: J Exp Med. 1971 Dec 1;134(6):1417-30
references.pmid: 4942406
references.citation: J Hyg (Lond). 1964 Jun;62:199-219
references.pmid: 14171271
references.citation: Clin Diagn Lab Immunol. 1997 May;4(3):321-7
references.pmid: 9144371