{'fraction_non_alphanumeric': 0.028053769725306838, 'fraction_numerical': 0.0, 'mean_word_length': 6.347639484978541, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Renal cathepsin G and angiotensin II generation

Background Alternative pathways of angiotensin II biosynthesis play a significant role in the renin–angiotensin system. In this study porcine renal tissue was investigated for angiotensin II-generating enzymes. Methods and results Protein extracts from porcine renal tissue were fractionated by liquid chromatography and tested for their angiotensin II-generating activity by the mass-spectrometry-assisted enzyme screening system (MES) and the active fractions were purified to near homogeneity. In one of these active fractions, inhibitable by an angiotensin-converting enzyme specific inhibitor, purified by anion-exchange chromatography, followed by hydroxyapatite chromatography, lectin affinity chromatography, size-exclusion chromatography and two-dimensional electrophoresis, angiotensin-converting enzyme was identified by a tryptic peptide matrix-assisted-laser-desorption/ionization (MALDI) mass fingerprint analysis. In a second active fraction, which was inhibited by chymostatin and antipain, yielded by anion-exchange chromatography, followed by hydroxyapatite chromatography, lectin affinity chromatography, chymostatin–antipain chromatography and one-dimensional electrophoresis, cathepsin G was identified by electro-spray ionization (ESI)-ion-trap mass spectrometry. The angiotensin-generating activities of the fraction containing angiotensin-converting enzyme and the fraction containing cathepsin G were in the same order of magnitude, thus showing that the contribution of cathepsin G towards the production of angiotensin II is significant. Conclusion This is the first time that cathepsin G has been identified in mammalian renal tissue.