Improvements of the Anson assay for measuring proteolytic activities in acidic pH range

✍ Scribed by Jo Lanoë; Jacques Dunnigan

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 614 KB
• Volume: 89
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(78)90375-5

✦ Synopsis

This paper proposes a modification of the classic Anson assay [Anson, M. L. (1939) J. Gen. Physiol. 22, 79-891 for proteolytic enzymes which are active in the acidic pH range; it abolishes many of the constraints common to this widely used method. The present procedure allows for: (i) the control of zymogen activation; (ii) the measurement of the hydrolyzed products on a very wide concentration range, due to their extended direct proportionality to both the incubation time and the enzyme concentration; (iii) the possibility to perform the assay at any given pH between 1.3 and 5.0 with minimal interference from ionic strength; (iv) a very simple conversion of the absorbance into proteolytic units, allowed by a better choice of TCA concentration. The method offers good sensitivity and is compared in detail to the original method and its various modifications.