Studies of optical rotatory dispersion (ORD) and circular dichroism (CD) are reported on pepsinogen, carbamyl-, and succinylpepsinogen. From the ORD measurements in the wave length range of 600 to 300 rnp as functions of urea, temperature, and pH, it was shown that the macromolecular conformation of the three proteins differs markedly. On replacing the e-NH2 groups of the lysine residues of pep...

The expression of a gene encoding an embryonic chick pepsinogen was investigated in developing avian gut. Expression is restricted to the epithelial layer of the embryonic proventriculus (glandular stomach). We can therefore regard this gene as a marker gene for proventricular epithelial differentiation. There is some considerable evidence in favour of epithelial-mesenchymal interactions being ...

The spontaneous and pepsin-catalyzed activation of pepsinogen has been observed and analyzed kinetically. At appropriate protein concentrations (1 mg per ml or less), a kinetically first order reaction was observed in the pH range 1 to 3, implying an intramolecular activation mechanism. Substantiation of the first order reaction came from a linear plot of log pepsinogen concentration versus tim...

Distribution and temporal change of free calcium concentration [( Ca2+]i) in single guinea pig gastric chief cells were visualized by a digital imaging microscope equipped with a microspectrofluorometer. The distribution was not homogeneous; a higher [Ca2+]i area was often localized in some restricted regions of the endoplasm and also at the peripheral cytoplasm just beneath the plasma membrane...

AIMS To clarify the relation between the serum titre of anti-Helicobacter pylori (H pylori) antibody and the extent of intestinal metaplasia of the gastric mucosa. METHODS The serum anti-H pylori IgG titres of 95 asymptomatic individuals (mean age 65 years) undergoing an annual health examination were measured and compared with the extent of intestinal metaplasia (absent, moderate, or extensi...

Chicken pepsinogen was extracted from the forestomach of chicken and purified by the consecutive application of acetone precipitation, chromatography on diethylaminoethyl cellulose, and gel filtration on Sephadex G-100. The purified pepsinogen was homogeneous on disc electrophoresis and sedimented as monodisperse material. Chicken pepsin was obtained by the activation of the pure zymogen at pH ...

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.

Activation of swine pepsinogen with chicken pepsin results in the formation of swine pepsin. Activation of chicken pepsinogen with swine pepsin results in the formation of chicken pepsin. The structure responsible for the species specificity of the enzyme is therefore present in the inactive precursor.