introduction : activated protein c (apc) inactivates factor v by cleavage of its heavy chain at arg306, arg506, arg679, and lys994. mutational changes, which abolish apc cleavage sites, may predispose thrombosis by altering the inactivation process of factor v.  factor v leiden (arg506glu) has been demonstrated as a strong risk factor for thrombosis. in the current study, we have studied whethe...

High-resolution mapping of topol cleavages in the regions of human DNA including the oncogene c-Ha-ras and p53, has revealed three kinds of topol cleavage sites: cleavage sites not affected by camptothecin; cleavage sites reinforced only in the presence of camptothecin, and cleavage sites which weaken in the presence of camptothecin. Statistical analysis of sequences revealed certain nucleotide...

The retroviral protease is a key enzyme in a viral multienzyme complex that initiates an ordered sequence of events leading to virus assembly and propagation. Viral peptides are initially synthesized as polyprotein precursors; these precursors undergo a number of proteolytic cleavages executed by the protease in a specific and presumably ordered manner. To determine the role of individual prote...

Cleavage of ADAMTS-18 by thrombin represents a new mechanism of platelet thrombus clearance via the release of active ~45-kDa C-terminal fragments that induces oxidative platelet fragmentation. The exact cleavage sites remain unclear, but Arg (R)775/Ser (S)776 in spacer region of ADAMTS-18 has been shown to be one of the cleavage sites of thrombin. Here, we demonstrate that R792/S793 and R823/S...

In this study, we further examined the sequence selectivity of camptothecin in mammalian topoisomerase I cDNA from human and Chinese hamster. In the absence of camptothecin, almost all the bases at the 3'-terminus of cleavage sites are T for calf thymus and wheat germ topoisomerase I. In addition, wheat germ topoisomerase I exhibits preference for C (or not T) at -3 and for T at -2 position. As...