PT - JOURNAL ARTICLE AU - Sakamoto, Shingo AU - Komatsu, Toru AU - Watanabe, Rikiya AU - Zhang, Yi AU - Inoue, Taiki AU - Kawaguchi, Mitsuyasu AU - Nakagawa, Hidehiko AU - Ueno, Takaaki AU - Okusaka, Takuji AU - Honda, Kazufumi AU - Noji, Hiroyuki AU - Urano, Yasuteru TI - Multiplexed single-molecule enzyme activity analysis for counting disease-related proteins in biological samples AID - 10.1126/sciadv.aay0888 DP - 2020 Mar 01 TA - Science Advances PG - eaay0888 VI - 6 IP - 11 4099 - http://advances.sciencemag.org/content/6/11/eaay0888.short 4100 - http://advances.sciencemag.org/content/6/11/eaay0888.full SO - Sci Adv2020 Mar 01; 6 AB - We established an ultrasensitive method for identifying multiple enzymes in biological samples by using a multiplexed microdevice-based single-molecule enzymatic assay. We used a paradigm in which we “count” the number of enzyme molecules by profiling their single enzyme activity characteristics toward multiple substrates. In this proof-of-concept study of the single enzyme activity–based protein profiling (SEAP), we were able to detect the activities of various phosphoric ester–hydrolyzing enzymes such as alkaline phosphatases, tyrosine phosphatases, and ectonucleotide pyrophosphatases in blood samples at the single-molecule level and in a subtype-discriminating manner, demonstrating its potential usefulness for the diagnosis of diseases based on ultrasensitive detection of enzymes.