N = 3).Lau et al. BMC Complementary and Option Medicine 2013, 13:313 http://biomedcentral/1472-6882/13/Page 9 ofInhibition pattern of ACE inhibitorsPeptide AHEPVK exhibited essentially the most potent ACE inhibitory activity (IC50 62.8 M) and it shows stability CDK7 Inhibitor Biological Activity against gastrointestinal digestion. Hence, it was chosen to identify its inhibition pattern against the ACE enzyme. According to the Lineweaver-Burk plot in Figure six, peptide AHEPVK showed a competitive inhibition pattern against the ACE. This suggests that the peptide may possibly bind for the active website of ACE to block it from binding for the substrate. In addition, ACE has been reported to show preference for competitive inhibitors that include a hydrophobic amino acid in the third position in the C-terminal [44,45]. That is in accordance using the amino acid sequence of AHEPVK which could possibly explain the competitive inhibition pattern exhibited by this peptide. The competitive inhibition pattern exhibited by AHEPVK is similar to ACE inhibitory peptides purified from the edible mushrooms G. frondosa, P. cornucopiae, P. adiposa and T. giganteum [18-21]. Also, a commercial ACE inhibitor and antihypertensive drug, captopril, also inhibits ACE in a competitive manner [4].Received: 19 March 2013 Accepted: six November 2013 Published: 11 NovemberConclusion In the present study, peptides isolated from P. cystidiosus were shown to be prospective ACE inhibitors. Peptide AHEPVK exhibited a high IC50 value (62.8 M) and its peptide sequence remained steady following gastrointestinal digestion. It exhibited a competitive inhibition pattern against ACE. Peptide GPSMR was predicted to release a dipeptide ACE inhibitor, GP, from its precursor just after gastrointestinal digestion. Despite the fact that these peptides had decrease ACE inhibitory activity in comparison with industrial antihypertensive drugs, they are derived from food sources and should really have no unwanted effects.Abbreviations ACE: Angiotensin I-converting enzyme; RPHPLC: Reverse phase high performance liquid chromatography; SEC: Size exclusion chromatography; LC-MS/MS: Liquid chromatography mass spectrometry. Competing interests The authors declare that they’ve no competing interests. Authors’ contributions CCL carried out all the experimentation, analysis of information and drafting on the manuscript. NA involved in monitoring and coordinating the perform on mushroom biology and antihypertensive activity. ASS involved in coordinating the operate on isolation and purification of peptides; and proteomic analysis. All authors study and authorized the final manuscript. Acknowledgements The authors would prefer to thank the University of Malaya (Grant PPP: PS238/ 2008C, PS478/2010B, PV073-2011B) plus the Ministry of Larger Education Malaysia (HIR-MOHE: F000002-21001) for monetary help for this project. Author details 1 Mushroom Study Centre, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia. 2Medical Biotechnology Laboratory, University of Malaya Centre for Proteomics Investigation (UMCPR), Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.References 1. van Vark LC, Bertrand M, Akkerhuis KM, Brugts JJ, Fox K, Mourad J-J, Boersma E: Caspase 2 Inhibitor Formulation Angiotensin-converting enzyme inhibitors lower mortality in hypertension: a meta-analysis of randomized clinical trials of renin-angiotensin-aldosterone method inhibitors involving 158 998 patients. Eur Heart J 2012, 33:2088097. 2. Erd EG: The ACE and I: how ACE inhibitors came to be.
