{'fraction_non_alphanumeric': 0.046886446886446886, 'fraction_numerical': 0.041025641025641026, 'mean_word_length': 4.377952755905512, '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}}
Partial purification and some properties of milk-clotting enzyme produced by Penicillium brevicompactum NRC-829.

Milk-clotting enzyme (MCE) produced by Penicillium brevicompactum NRC-829 was partially purified and characterized. Purification was about 7.8 and 22-fold using ion-exchange TEAE-cellulose and Sephadex G-100 chromatographic columns, and specific activities were about 514 and 1434 U/mg protein, respectively. The molecular weight of the enzyme was about 50.0 kDa. The enzyme acts optimally at 65 °C, and is stable up to 60 °C for 10 min. The purified enzyme is an acid protease with optimum pH of 5.75, and retains 65% of residual activity between pH 5-6. Ca 2+ was found to be a potent activator with 330% increase in milk-clotting activity compared to control (in absence of metal ions). The substrate concentration gave a hyperbolic response. The Lineweaver-Burk plot showed a K m value of 5 mg/ml, when skim-milk was used as substrate. The ratio of milk-clotting activity (MCA) to proteolytic activity (PA) was 14 to 10.5 at pH6, respectively. A gradual reduction of the activity was observed by increasing Na + concentration between 5-100 μmoles. However, Mn 2+ , Zn 2 , + Fe 3+ and Cu 2+ had a stimulating effect on the purified enzyme. A complete inhibition occurred with addition of Ag + , Hg 2+ , iodoacetate or EDTA to the reaction mixtures.