The relationship between glandular kallikrein and growth factor-processing proteases of mouse submaxillary gland

Postnatal development of trypsin-like esteroproteases in mouse submandibular gland

The development of trypsin-like esteroproteases in the submandibular gland of mice was studied, using a newly synthesized naphthyl ester (tosyl-L-lysine alpha-naphthyl ester) for the preparation of zymograms and for histochemical demonstration of the enzyme. Esteroprotease activities were first detected spectrophotometrically on day 15 after birth; then increased markedly after day 20. A sex difference in esteroprotease activity appeared on day 25. Zymograms prepared after isoelectric focusing in polyacrylamide slab gels showed that the glands of neonatal mice contained esteroproteases with a rather different composition from that of adult mice. The adult type isozymes appeared first on day 15, and their activities increased markedly after day 20. Histochemical studies revealed that the isozymes of neonatal mice were derived from mast cells. A few striated ducts were first stained on day 15, and the sex difference of the granular tubules became obvious on day 25. These results indicate that the development of trypsin-like esteroproteases faithfully reflects the differentiation of granular tubules in the mouse submandibular gland, except in the neonatal period.

Isolation and partial amino acid sequence analysis of nerve growth factor from the guinea pig prostate

Nerve growth factor (NGF) has been purified from the guinea pig prostate using a modification of the Bocchini-Angeletti method for isolating 2.5S NGF from mouse submaxillary glands. As with the mouse preparation, guinea pig prostate NGF appears to migrate as a high molecular weight entity at physiological pH. Following dissociation, NGF, active in neurite proliferation assays and similar in size to mouse 2.5S NGF, can be isolated by chromatography on a column of carboxymethyl-cellulose at pH 4.8. Based on gel filtration, SDS-polyacrylamide gel analysis, and amino-terminal sequence studies, this material consists of two, noncovalently linked, identical polypeptide chains each with a molecule weight of about 13,000. The amino-terminal third of the polypeptide chain is at 90% identical to the corresponding region of the murine molecule, confirming the homology of the guinea pig prostate protein to NGFs obtained from different tissues in other species. However, in contrast to the mouse preparation, the putative high molecular weight form of guinea pig NGF does not contain a subunit with arginine esteropeptidase activity. Although there is an abundance of this enzymatic activity in the homogenate, it does not appear to be associated with the fractions containing NGF. This apparent difference in the mouse and guinea pig material is of interest because the mouse gamma subunit, possessing the arginine esteropeptidase activity, has been alleged to participate in the processing of a precursor of the beta NGF polypeptide chain.

Isolation and characterization of human urinary kallikrein

Human urinary kallikrein was purified by gel filtration on Sephacryl S-200 and affinity chromatography on aprotinin-Sepharose, followed by ion exchange chromatography on DEAE-Sepharose. Thus an enzyme preparation with a specific activity (using AcPheArgOEt as substrate) of 1 100 U/mg protein was obtained. A specific bioligical activity of 2 300 KE/mg was measured in the dog blood pressure assay and of 0.742 HMW kininogen-U/mg, corresponding to the liberation of 787 micrograms bradykinin per mg enzyme per min from HMW-kininogen, in the rat uterus assay. In dodecyl sulfate electrophoresis two protein bands with apparent molecular weights of 41 000 and 34 000 were separated. The amino acid composition was determined and isoleucine was identified as the only aminoterminal amino acid. On isoelectric focusing six protein bands with isoelectric points of 3.75, 3.80, 3.90, 4.00, 4.05 and 4.25 were separated. The kinetic constants for the kallikrein-catalyzed hyrdolysis of AcPheArgOEt and D ValLeuArgNHNp were determined. The bimolecular velocity constant for the inhibition by diisopropyl fluorophosphate was determined as 9 +/- 2l x mol-1 x min-1. Immunological studies showed that a close relationship exists between the urinary enzyme and other human glandular kallikreins. Deoxycholate, lysolecithin and other amphiphiles activated human urinary kallikrein.