Beta-D-glucoside utilization by Mycoplasma mycoides subsp. mycoides SC: possible involvement in the control of cytotoxicity towards bovine lung cells

Vilei, Edy M; Correia, Ivone; Ferronha, M Helena; Bischof, Daniela F; Frey, Joachim (2007). Beta-D-glucoside utilization by Mycoplasma mycoides subsp. mycoides SC: possible involvement in the control of cytotoxicity towards bovine lung cells. BMC microbiology, 7, p. 31. London: BioMed Central 10.1186/1471-2180-7-31

[img]
Preview
Text
3.pdf - Published Version
Available under License Creative Commons: Attribution (CC-BY).

Download (1MB) | Preview

BACKGROUND: Contagious bovine pleuropneumonia (CBPP) caused by Mycoplasma mycoides subsp. mycoides small-colony type (SC) is among the most serious threats for livestock producers in Africa. Glycerol metabolism-associated H2O2 production seems to play a crucial role in virulence of this mycoplasma. A wide number of attenuated strains of M. mycoides subsp. mycoides SC are currently used in Africa as live vaccines. Glycerol metabolism is not affected in these vaccine strains and therefore it does not seem to be the determinant of their attenuation. A non-synonymous single nucleotide polymorphism (SNP) in the bgl gene coding for the 6-phospho-beta-glucosidase (Bgl) has been described recently. The SNP differentiates virulent African strains isolated from outbreaks with severe CBPP, which express the Bgl isoform Val204, from strains to be considered less virulent isolated from CBPP outbreaks with low mortality and vaccine strains, which express the Bgl isoform Ala204. RESULTS: Strains of M. mycoides subsp. mycoides SC considered virulent and possessing the Bgl isoform Val204, but not strains with the Bgl isoform Ala204, do trigger elevated levels of damage to embryonic bovine lung (EBL) cells upon incubation with the disaccharides (i.e., beta-D-glucosides) sucrose and lactose. However, strains expressing the Bgl isoform Val204 show a lower hydrolysing activity on the chromogenic substrate p-nitrophenyl-beta-D-glucopyranoside (pNPbG) when compared to strains that possess the Bgl isoform Ala204. Defective activity of Bgl in M. mycoides subsp. mycoides SC does not lead to H2O2 production. Rather, the viability during addition of beta-D-glucosides in medium-free buffers is higher for strains harbouring the Bgl isoform Val204 than for those with the isoform Ala204. CONCLUSION: Our results indicate that the studied SNP in the bgl gene is one possible cause of the difference in bacterial virulence among strains of M. mycoides subsp. mycoides SC. Bgl does not act as a direct virulence factor, but strains possessing the Bgl isoform Val204 with low hydrolysing activity are more prone to survive in environments that contain high levels of beta-D-glucosides, thus contributing in some extent to mycoplasmaemia.

Item Type:

Journal Article (Original Article)

Division/Institute:

05 Veterinary Medicine > Department of Infectious Diseases and Pathobiology (DIP) > Institute of Veterinary Bacteriology

UniBE Contributor:

Vilei, Edi; Bischof, Daniela and Frey, Joachim

ISSN:

1471-2180

Publisher:

BioMed Central

Language:

English

Submitter:

Factscience Import

Date Deposited:

04 Oct 2013 14:53

Last Modified:

05 Dec 2014 23:08

Publisher DOI:

10.1186/1471-2180-7-31

PubMed ID:

17439646

Web of Science ID:

000246364300001

BORIS DOI:

10.7892/boris.22356

URI:

https://boris.unibe.ch/id/eprint/22356 (FactScience: 34300)

Actions (login required)

Edit item Edit item
Provide Feedback