Magro, A. J.Soares, A. M.Giglio, JRFontes, MRM2014-05-202014-05-202003-11-21Biochemical and Biophysical Research Communications. San Diego: Academic Press Inc. Elsevier B.V., v. 311, n. 3, p. 713-720, 2003.0006-291Xhttp://hdl.handle.net/11449/17603Phospholipases A(2) are components of Bothrops venoms responsible for disruption of cell membrane integrity via hydrolysis of its phospholipids. A class of PLA(2)-like proteins has been described which despite PLA(2) activity on artificial substrate, due to a D49K mutation, is still highly myonecrotic. This work reports the X-ray structure determination of two Lys49-PLA(2)s from Bothrops neuwiedi pauloensis (BnSP-7 and BnSP-6) and, for the first time, the comparison of eight dimeric Lys49-PLA2s. This comparison reveals that there are not just two (open and closed) but at least six different conformations. The binding of fatty acid observed in three recent Lys49-PLA(2) structures seems to be independent of their quaternary conformation. Cys29 polarization by Lys122 is not significant for BnSP-7 and BnSP-6 or other structures not bound by fatty acids. These structures may be in an active state when nothing is bound to them and the Lys122/Cys29 interactions are weak or absent. (C) 2003 Elsevier B.V. All rights reserved.713-720engphospholipase A(2)myotoxincrystal structurebothropic venomquaternary structure changeslack of catalytic mechanismArtigo10.1016/j.bbrc.2003.10.047WOS:000186643100026Acesso restrito