Conversion of pepsinogen into pepsin is not a one-step process.
نویسندگان
چکیده
By incubation of pepsinogen with pepstatin at pH2.5, the first 'active' protein generated on activation is trapped in an inactive complex. The first activation peptide liberated has been identified as residues 1-16 from the pepsinogen sequence. This suggests a sequential mechanism rather than a one-step formation of pepsin.
منابع مشابه
Intramolecular activation of porcine pepsinogen.
Conversion of pepsinogen to pepsin at acid pH involves an intramolecular reaction in which the unproteolyzed zymogen cleaves itself. This conclusion is based upon experiments in which pepsinogen, at low concentrations, was activated in the presence of substrate, hemoglobin. Under these conditions, the activation of pepsinogen is independent of pepsinogen concentration, and addition of pepsin do...
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The conversion of pepsinogen to pepsin has been followed by means of the fluorescent probe, Z-p-toluidinonaphthalene6-sulfonate (TNS). It was found that the change in fluorescence accurately reflects the formation of active pepsin. The data on the binding of TNS to pepsinogen and pepsin suggest that the environment surrounding the fluorophore is altered during the conversion. One of the peptide...
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 153 1 شماره
صفحات -
تاریخ انتشار 1976