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In the duodenum, the pancreatic zymogens, trypsinogen, chymotrypsinogen, proelastase and procarboxypeptidase, are converted into active enzymes by enteropeptidase and trypsin. Chymotrypsinogen, a single polypeptide chain of 245 amino acids residues, is converted to alpha-chymotrypsin, which has three
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partially activates it. Another partially inactivated pepsinogen completes the activation by removing the peptide, turning the pepsinogen into pepsin. Accidental activation of zymogens can happen when the secretion duct in the pancreas is blocked by a
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Another way that enzymes can exist in inactive forms and later be converted to active forms is by activating only when a
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polypeptide chains linked by two of the five disulfide bond present in the primary structure of chymotrypsinogen.
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than inside the fungal cell and this changes the zymogen's structure into an active enzyme.
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Molecular mechanisms for the conversion of zymogens to active proteolytic enzymes
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secretes zymogens partly to prevent the enzymes from digesting proteins in the
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extensions of the enzyme or a "prosegment" often aid in the stabilization and
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in order to activate it. The inactivating piece which is cleaved off can be a
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into the environment as zymogens. The external environment has a different
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Gastroenterology: Pathophysiology and
Clinical Applications
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438:"CHAPTER 4 - Functional Characteristics of the Stomach"
121:. A zymogen requires a biochemical change (such as a
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481:"Life Sciences, Fundamentals and Practice, Part I"
149:. Although they limit the enzyme's ability, these
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168:in which they are synthesised. Enzymes like
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253:(examples, prothrombin, or plasminogen)
141:unit, or can be independently-folding
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450:10.1016/b978-0-409-95021-2.50009-1
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479:Mina U, Kumar P (January 2016).
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16:Inactive precursor to an enzyme
386:Merriam-Webster.com Dictionary
330:Merriam-Webster.com Dictionary
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256:Some of the proteins of the
157:of the enzyme they inhibit.
172:are created in the form of
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508:Zymogens - Washington.edu
436:Dworken HJ (1982-01-01).
145:comprising more than 100
283:Procarboxypolypeptidases
419:Oxford University Press
363:Oxford University Press
230:Examples of zymogens:
125:reaction revealing the
415:UK English Dictionary
359:UK English Dictionary
249:Most proteins in the
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180:release it into the
533:Precursor proteins
251:coagulation system
113:), is an inactive
459:978-0-409-95021-2
389:. Merriam-Webster
333:. Merriam-Webster
258:complement system
205:digestive enzymes
186:hydrochloric acid
68:), also called a
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240:Chymotrypsinogen
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195:pancreatitis
182:gastric acid
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131:Golgi bodies
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21:biochemistry
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408:"proenzyme"
381:"proenzyme"
273:Proelastase
263:Procaspases
235:Trypsinogen
178:chief cells
127:active site
522:Categories
490:2020-12-15
465:2020-12-15
393:2016-01-24
337:2016-01-24
311:References
305:Prohormone
268:Pacifastin
245:Pepsinogen
174:pepsinogen
151:N-terminal
123:hydrolysis
352:"zymogen"
325:"zymogen"
278:Prolipase
191:gallstone
115:precursor
70:proenzyme
538:Zymogens
289:See also
226:Examples
216:cofactor
184:, whose
162:pancreas
147:residues
528:Enzymes
300:Protein
155:folding
143:domains
139:peptide
135:cleaved
25:zymogen
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413:Lexico
357:Lexico
295:Enzyme
170:pepsin
119:enzyme
117:of an
201:Fungi
166:cells
454:ISBN
160:The
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