Proteins with an RTX motif share a common, ATP-dependent mechanism for this process. Proteins with an LPXTG motif that have undergone this process are then cleaved by sortases. A “passenger” domain allows some proteins to perform this process on themselves. An N-terminal motif containing a pair of “twin” arginine residues acts as a signal for this process in the Tat pathway. One system for this process consists of a “needle” complex attached to a (*) basal body. H. pylori’s system for this process is evolutionarily related to the machinery for conjugation, while Shigella’s system for this process is sometimes called the “injectisome” and structurally resembles flagella. For 10 points, some bacteria use “type III” and “type IV” systems to accomplish what process of exporting a protein from a cell, exemplified by the release of hormones from endocrine glands? ■END■
ANSWER: secretion [accept translocation; prompt on descriptive answers indicating that a protein is being moved across the cell membrane; reject any descriptive answers involving the membrane of something other than the cell, like “moving stuff into the endoplasmic reticulum” or “moving stuff into the mitochondria”]
<Billy Busse, Biology>
= Average correct buzz position