Identification, in silico screening, and molecular docking of novel ACE inhibitory peptides isolated from the edible symbiot Boletus griseus-Hypomyces chrysospermus

The aim of this study is to find angiotensin-I-converting enzyme inhibitory (ACEI) peptides from the edible symbiot Boletus griseus-Hypomyces chrysospermus (BGHC). The peptides from the methanol extract of BGHC were identified through ultraperformance liquid chromatography quadrupole Orbitrap tandem mass spectrometry analysis coupled with de novo sequencing by using Peak Studio software. Subsequently, two ACEI peptides, being KYPHVF and LFRPE, were screened on the basis of PeptideRanker and the AHTpin online server. The in silico absorption, distribution, metabolism, excretion and toxicities (ADMET) of the two peptides were predicted with AdmetSAR software, and the two peptides showed good absorption and nontoxicity. Meanwhile, the ACEI mechanism of KYPHVF and LFRPE was analyzed through molecular docking with SYBYL-X 2.0 software. The molecular docking study revealed that the total scores of the interactions of KYPHVF and LFRPE with ACE were 12.53 and 11.34, respectively. KYPHVF and LFRPE could establish hydrogen bonds and hydrophobic interactions with the active site of ACE. Furthermore, the ACEI activities of KYPHVF and LFRPE were determined in vitro with the IC50 values of 5.99 and 58.15 mu mol/L, respectively.