Acid hydrolases fusion

The degradation of proteins by acid hydrolases in lysosomes involves vesicle fusion through three main pathwaysautophagy, endocytosis, and phagocytosis. The low pH inside lysosomes is maintained by an ATP driven proton pump. 

A P450-Hydrolase Fusion in Mycophenolic Acid Synthesis... 

Any detailed discussion of these individual phases must be speculative, but is valuable because of the critical importance of membrane fusion in the control of acid hydrolase activity in the lysosome-vacuolar apparatus. 

In addition to the commonly used TEV and 3 c proteases, several other proteases are commonly used to remove fusion tags (see Table 2). There are also other tag removal systems that do not rely on proteases. For example, the intein system is an autocatalytic cleavage of the produced fusion protein.297 For SUMO fusion proteins there are several hydrolases available for tag removal. Because the SUMO hydrolases recognize the whole fold of the tag and not just an amino acid sequence, they are highly specific and not prone to unintended cleavage.94 296... 

Involvement of a natural fusion of a eyto-ehrome P4S0 and a hydrolase in mycophenolie acid biosynthesis. Appl Environ Microbiol 78 4908-4913... 

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