Authors: N. Chaudhary
Abstract: Biochemical Investigations were carried out to ascertain some properties of acid phosphatases (ACPs) extracted from Pisum sativum and Triticum aestivum cotyledons named as ACP I and ACP II, respectively. The phosphatases obtained from the two sources were thermally stable (up to 700C) and displayed acidic activities by using para-nitrophenyl phosphate as substrate. The specific activities of ACP I and ACP II were 81.9 and 42.6 unitsmg-1 with Km values of 2.85 and 2.50 mM, respectively. Values of temperature coefficients (Q10) and activation energy (Ea) were found to be 1.7, 1.5 and 44.7, 40.6 kJmol-1 for ACP I and ACP II, respectively. ACP II activity was enhanced by Mg2+, Mn2+, Tween-20 and Cween-20. All the cations tested had slight inhibitory effect on ACP I. Sodium Lauryl Sulphate (SLS) acted as strong inhibitor of both; ACP I and ACP II, with inhibition constants (Ki) 4.6 x 10-4 and 5.5 x 10-4 M, respectively. ACP II was inhibited by most metals (except Mg2+, Mn2+) but the most powerful inhibitors were Cu2+ (uncompetitive) and Fe2+ (non-competitive) with Ki values 8.7 x 10-5 and 2.5 x 10-5 M, respectively. These results suggest that the acid phosphatases (ACP I and ACP II) play an important role in energy transfer; release of inorganic phosphate and also due to thermostability might act as potential biocatalysts for bio-industrial applications.
Keywords: Acid phosphatase, Pisum sativum, Thermostable, Triticum aestivum