Lee Heeyoung, Tran Minh-Hai, Jeong Hae Kyung, Han Jinwoo, Jang Sei-Heon, Lee ChangWoo
Department of Biomedical Science, Daegu University, Gyeongsan 712-714, South Korea; Center for Bio-Nanomaterials, Daegu University, Gyeongsan 712-714, South Korea.
Center for Bio-Nanomaterials, Daegu University, Gyeongsan 712-714, South Korea; Department of Physics, Daegu University, Gyeongsan 712-714, South Korea.
Anal Biochem. 2014 Apr 15;451:31-4. doi: 10.1016/j.ab.2014.01.017. Epub 2014 Feb 6.
In this article, we report the intrinsic catalytic activity of graphene oxide (GO) for the nonspecific cleavage of proteins. We used bovine serum albumin (BSA) and a recombinant esterase (rEstKp) from the cold-adapted bacterium Pseudomonas mandelii as test proteins. Cleavage of BSA and rEstKp was nonspecific regarding amino acid sequence, but it exhibited dependence on temperature, time, and the amount of GO. However, cleavage of the proteins did not result in complete hydrolysis into their constituent amino acids. GO also invoked hydrolysis of p-nitrophenyl esters at moderate temperatures lower than those required for peptide hydrolysis regardless of chain length of the fatty acyl esters. Based on the results, the functional groups of GO, including alcohols, phenols, and carboxylates, can be considered as crucial roles in the GO-mediated hydrolysis of peptides and esters via general acid-base catalysis. Our findings provide novel insights into the role of GO as a carbocatalyst with nonspecific endopeptidase activity in biochemical reactions.
