3640
Biochemistry 2010, 49, 3640–3647 DOI: 10.1021/bi100328j
Evidence for a Bicarbonate “Escort” Site in Haemophilus influenzae β-Carbonic Anhydrase†,‡ Roger S. Rowlett,* Katherine M. Hoffmann, Hannah Failing, Margaret M. Mysliwiec, and Dejan Samardzic Department of Chemistry, Colgate University, 13 Oak Drive, Hamilton, New York 13346 Received March 4, 2010; Revised Manuscript Received March 31, 2010 ABSTRACT: The Haemophilus influenzae β-carbonic anhydrase (HICA) allosteric site variants V47A and G41A were overexpressed and purified to homogeneity. These variants have kcat/Km values similar to that of the wild-type enzyme and exhibit a similar dramatic decrease in catalytic activity at pH
