Purification of horse renal kallikrein and chemical relations with horse urinary kallikrein.

This research involved the extraction and purification of a protein known as kallikrein from horse kidneys. After doing so, the researchers compared the purified kidney kallikrein to previously purified kallikrein from horse urine in order to study their biochemical relations. Findings revealed that the varying molecular weights of renal and urinary kallikrein result from the different purification methods used.

Purification Procedures

• The study began with the extraction and purification of kallikrein from horse kidneys, a process conducted using a series of chromatographic steps and affinity chromatography on Sepharose-Concanavaline.
• For comparison, the researchers used horse urinary kallikrein that had been previously purified through a separate process involving DE-32 hydroxylapatite and Sephadex G-100 gel filtration.

Research Findings

• Once purified, the final samples of renal (kidney) and urinary kallikrein were examined to determine the amino acid composition and the molecular weight as measured through gel electrophoresis.
• The researchers found that the ratio between each corresponding amino acid residue in the renal and urinary kallikrein was approximately 1.00 ± 0.30. Except for proline, half-cystine, and basic amino acid residues, a good proportion was achieved, indicating a significant degree of consistency in the amino acid composition of the two types of kallikrein.

Conclusions

• The research ultimately determined that the different molecular weight of renal and urinary kallikrein (47,500 and 28,000 respectively) is a result of the different purification procedures used, not a unique characteristic of the kallikrein originating from different bodily sources. This implies that the purification process can significantly alter the properties of the kallikrein, which could have implications for future biochemical research or potential medical applications.