|Name:||Small Hepatitis B Surface Antigen (HBsAg)|
|Puzzle:||Freestyle Design 500|
This protein is the smallest of the hepatitis B surface proteins, containing solely the S-domain. Historically, it also has been referred to as the Australia antigen (Au antigen). It is highly hydrophobic, containing four-transmembrane spanning regions. The HBsAg contains a high number of cysteines,14 all together, each of which is cross-linked to one another. It also may be glycosylated at Asp146.
HBsAg Sequence (226 amino acids):
1 mesttsgflg pllvlqagff lltriltipq sldswwtsln flggaptcpg qnsqsptsnh
Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease. The virus is transmitted through contact with the blood or other body fluids of an infected person. Two billion people worldwide have been infected with the virus and about 600 000 people die every year due to the consequences of hepatitis B. The hepatitis B virus is 50 to 100 times more infectious than HIV. Hepatitis B is an important occupational hazard for health workers. Hepatitis B is preventable with the currently available safe and effective vaccine.