Premium
Structural insights into the difference in substrate recognition of two mannoside phosphorylases from two GH 130 subfamilies
Author(s) -
Ye Yuxin,
Saburi Wataru,
Odaka Rei,
Kato Koji,
Sakurai Naofumi,
Komoda Keisuke,
Nishimoto Mamoru,
Kitaoka Motomitsu,
Mori Haruhide,
Yao Min
Publication year - 2016
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1002/1873-3468.12105
Subject(s) - substrate (aquarium) , glycogen phosphorylase , glycoside hydrolase , stereochemistry , chemistry , hydrolase , hydrogen bond , enzyme , molecule , biochemistry , biology , organic chemistry , ecology
In Ruminococcus albus , 4‐ O ‐β‐ d ‐mannosyl‐ d ‐glucose phosphorylase ( Ra MP 1) and β‐(1,4)‐mannooligosaccharide phosphorylase ( Ra MP 2) belong to two subfamilies of glycoside hydrolase family 130. The two enzymes phosphorolyze β‐mannosidic linkages at the nonreducing ends of their substrates, and have substantially diverse substrate specificity. The differences in their mechanism of substrate binding have not yet been fully clarified. In the present study, we report the crystal structures of Ra MP 1 with/without 4‐ O ‐β‐ d ‐mannosyl‐ d ‐glucose and Ra MP 2 with/without β‐(1→4)‐mannobiose. The structures of the two enzymes differ at the +1 subsite of the substrate‐binding pocket. Three loops are proposed to determine the different substrate specificities. One of these loops is contributed from the adjacent molecule of the oligomer structure. In Ra MP 1, His245 of loop 3 forms a hydrogen‐bond network with the substrate through a water molecule, and is indispensible for substrate binding.