| Title |
Catabolite Control Protein A of Streptococcus suis Type 2 Contributes to Sugar Metabolism and Virulence |
| Author |
Yulong Tang, Wei Wu, Xiaoyan Zhang, Zhongyan Lu, Jianshun Chen, and Weihuan Fang* |
| Address |
Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310058, P. R. China |
| Bibliography |
Journal of Microbiology, 50(6),994-1002, 2012,
|
| DOI |
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| Key Words |
Streptoccoccus suis type 2, catabolite control protein A, carbon catabolite repression, virulence |
| Abstract |
Catabolite control protein A (CcpA) is the major transcriptional regulator in carbon catabolite repression in several Gram-positive bacteria. We attempted to characterize the role of a CcpA homologue of Streptococcus suis type 2 in sugar
metabolism and virulence. Addition of glucose or sucrose to the defined medium significantly reduced the activity of raffinose-inducible α-galactosidase, cellobiose-inducible β-glucosidase, and maltose-inducible α-glucosidase of the wildtype
strain by about 9, 4, and 2-3 fold, respectively. Deletion of ccpA substantially derepressed the effects of repressing sugars on α-galactosidase or β-glucosidase activity. The ccpA deletion mutant showed reduced expression of virulence genes sly and eno (P<0.05), decreased adhesion to and invasion into endothelial cells (P<0.05), and attenuated virulence to mice with significant reduction of death rate and bacterial burden in organs, as compared to the wild-type strain. Both the in vitro and in vivo defect phenotypes were reversible by ccpA complementation. Thus, this study shows that CcpA of S. suis type 2 plays an important role in carbon catabolite repression and virulence. |
