Identification of a 57 kDa membrane protein for group A Streptococcus

• Main Authors: Cheng- Yi, 莊政益
• Other Authors: Ling-Yun Chen
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/72167428705940250426

碩士 === 中山醫學大學 === 生化暨生物科技研究所 === 95 === Streptococcus pyogenes, also called group A streptococcus (GAS), is a Gram-positive bacterium. GAS can cause infectious diseases in skin or throat of human, including uncomplicated pharygitis and scarlet fever, and develop into severe complications , including necrotizing fasciitis, sepsis and streptococcal toxic shock syndrome. GAS can induce virulence factor expression such as M protein and C5a peptidase and increase invation、infection and immune evasion of host cells and tissue.In our previous study, we found hat M.W.57kDa protein of GAS can be recognized by adult serum but poorly recognized by children serum (the <14 years old serum). This result is association with distribution of age from CDC report. In our previous study,it is not effective to purify various membrane protein with anion affinity chromatography column DE-52、High Q and hydrophobic interaction phenyl column.In this study,we exploit a new strategy to searching for method of extraction and purification for M.W.57kDa protein of GAS. At first,we get extraction solution of M.W.57kDa protein of GAS by using heating.The next, we get a great quantity of purified protein by using anion affinity chromatography column High Q. At last, we found this protein is M protein serotype 12 precursor by usig MALDI-TOF identify. This finding will help us further studying in the future and can be used as tool of early diagnosis.