Characterization of the gene for an immunodominant 72 kDa lipoprotein of Mycoplasma mycoides subsp. mycoides small colony type

Microbiology ◽  
1996 ◽  
Vol 142 (12) ◽  
pp. 3515-3524 ◽  
Author(s):  
X. Cheng ◽  
J. Nicolet ◽  
R. Miserez ◽  
P. Kuhnert ◽  
M. Krampe ◽  
...  
2002 ◽  
Vol 184 (13) ◽  
pp. 3712-3722 ◽  
Author(s):  
Anja Persson ◽  
Karin Jacobsson ◽  
Lars Frykberg ◽  
Karl-Erik Johansson ◽  
François Poumarat

ABSTRACT A variable surface protein, Vmm, of the bovine pathogen Mycoplasma mycoides subsp. mycoides small colony type (M. mycoides SC) has been identified and characterized. Vmm was specific for the SC biotype and was expressed by 68 of 69 analyzed M. mycoides SC strains. The protein was found to undergo reversible phase variation at a frequency of 9 × 10−4 to 5 × 10−5 per cell per generation. The vmm gene was present in all of the 69 tested M. mycoides SC strains and encodes a lipoprotein precursor of 59 amino acids (aa), where the mature protein was predicted to be 36 aa and was anchored to the membrane by only the lipid moiety, as no transmembrane region could be identified. DNA sequencing of the vmm gene region from ON and OFF clones showed that the expression of Vmm was regulated at the transcriptional level by dinucleotide insertions or deletions in a repetitive region of the promoter spacer. Vmm-like genes were also found in four closely related mycoplasmas, Mycoplasma capricolum subsp. capricolum, M. capricolum subsp . capripneumoniae, Mycoplasma sp. bovine serogroup 7, and Mycoplasma putrefaciens. However, Vmm could not be detected in whole-cell lysates of these species, suggesting that the proteins encoded by the vmm-like genes lack the binding epitope for the monoclonal antibody used in this study or, alternatively, that the Vmm-like proteins were not expressed.


2010 ◽  
Vol 142 (3-4) ◽  
pp. 285-292 ◽  
Author(s):  
Shamoon Naseem ◽  
Jochen Meens ◽  
Joerg Jores ◽  
Martin Heller ◽  
Stefan Dübel ◽  
...  

1998 ◽  
Vol 59 (2-3) ◽  
pp. 109-122 ◽  
Author(s):  
El-Mostafa Abdo ◽  
Jacques Nicolet ◽  
Raymond Miserez ◽  
Rosario Gonçalves ◽  
José Regalla ◽  
...  

1976 ◽  
Vol 22 (7) ◽  
pp. 942-948 ◽  
Author(s):  
M. C. Cadmus ◽  
S. P. Rogovin ◽  
K. A. Burton ◽  
J. E. Pittsley ◽  
C. A. Knutson ◽  
...  

Stock cultures of Xanthomonas campestris NRRL B-1459 require special attention to maintenance and propagation to assure consistent production in good yields of the extracellular polysaccharide xanthan. Under customary conditions of propagative maintenance on agar slants, variant colony types develop that are smaller in size than the normal type. The rate of regression of the normal to the variant forms was diminished when the D-glucose content of the stock medium was sufficient to avoid depletion during storage and when transfer to fresh medium was reduced to 14-day intervals. Under conditions for polysaccharide production, the normal large-colony type gives crude culture liquors after 48 h of 7000 centipoise (cp) viscosity; the predominant variant form gives only 4000 cp. On the basis of 2.1% initial D-glucose, biopolymer yields for the normal and variant strains were 62 and 43%, respectively. Polysaccharide produced by the variant (small-colony type) differs adversely in solution properties from that of the parent strain (large-colony type); it differs also in its lower content of pyruvic acid and O-acetyl substituents. The molar ratios of constituent sugars (D-glucose, D-mannose, and D-glucuronic acid), however, were identical in polysaccharides with the normal and variant strains. Exclusion of colonial variants from fermentations is prerequisite to production of xanthan optimum in properties and yield.


2000 ◽  
Vol 38 (4) ◽  
pp. 1419-1425 ◽  
Author(s):  
John B. March ◽  
Jason Clark ◽  
Malcolm Brodlie

Four strains of Mycoplasma mycoides subsp.mycoides small colony type (MmmSC) isolated from recent outbreaks of contagious bovine pleuropneumonia (CBPP) in Africa have been investigated. One Botswanan strain, M375, displayed numerous and significant phenotypic differences from both contemporary field isolates and older field and vaccine strains (African, Australian, and European strains dating back to 1936). Differences include altered morphology, reduced capsular polysaccharide production, high sensitivity to MmmSC rabbit hyperimmune antisera in vitro, and unique polymorphisms following immunoblotting. While insertion sequence analysis using IS1634 clearly indicates a close evolutionary relationship to west African strains, hybridization with IS1296 shows the absence of a band present in all other strains of MmmSC examined. The data suggest that a deletion has occurred in strain M375, which may explain its altered phenotype, including poor growth in vitro and a relative inability to cause septicemia in mice. These characteristics are also exhibited byMycoplasma capricolum subsp. capripneumoniae(causal agent of contagious caprine pleuropneumonia [CCPP]), against which M375 antiserum exhibited some activity in vitro (unique among the various MmmSC antisera tested). These findings may have evolutionary implications, since CCPP is believed to be lung specific and without a septicemic phase (unlike CBPP). Since M375 was isolated from a clinical case of CBPP, this novel biotype may be fairly widespread but not normally isolated due to difficulty of culture and/or a potentially altered disease syndrome. Bovine convalescent antisera (obtained from contemporary naturally infected cattle in Botswana) were active against strain M375 in an in vitro growth inhibition test but not against any other strains of MmmSC tested. There exists the possibility therefore, that strain M375 may possess a set of protective antigens different from those of other strains of MmmSC (including vaccine strains). These findings have implications for the control of the current CBPP epidemic in Africa.


1999 ◽  
Vol 181 (4) ◽  
pp. 1319-1323 ◽  
Author(s):  
Edy M. Vilei ◽  
Jacques Nicolet ◽  
Joachim Frey

ABSTRACT A new insertion sequence, IS1634, has been identified in Mycoplasma mycoides subsp. mycoidessmall-colony type (SC). IS1634 shows structural and functional similarities to IS1549 of Mycobacterium smegmatis and with it seems to form a new class or family of insertion sequences. IS1634 has a size of 1,872 bp, including two 13-bp terminal inverted repeats. It contains an open reading frame (ORF) encoding a product of 533 amino acids which shows similarity to the transposase of IS1549 and to a lesser extent to the transposases of IS elements of the IS4family. IS1634 is present at about 30 copies in the genome of all 22 different field strains of M. mycoides subsp. mycoides SC tested. Characteristic of IS1634 are the long and variable-length direct repeats at the sites of insertion which were found to reach up to about 500 bp. IS1634 is specific to M. mycoides subsp. mycoides SC and is not present in any of the other members of the M. mycoidescluster. Neither was it found in other closely relatedMycoplasma species of ruminants.


2005 ◽  
Vol 49 (12) ◽  
pp. 5162-5165 ◽  
Author(s):  
R. D. Ayling ◽  
S. Bisgaard-Frantzen ◽  
J. B. March ◽  
K. Godinho ◽  
R. A. J. Nicholas

ABSTRACT In vitro minimum inhibitory concentrations were determined for 21 antimicrobials against 41 isolates of Mycoplasma mycoides subsp. mycoides small-colony type, the cause of contagious bovine pleuropneumonia. Of the antimicrobials used most widely in Africa, oxytetracycline and tilmicosin were effective, while the isolates were resistant to tylosin. These results provide a baseline for monitoring antimicrobial resistance.


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