Crystallographic studies of the interactions of Escherichia coli lytic transglycosylase Slt35 with peptidoglycan

Citation
Ej. Van Asselt et al., Crystallographic studies of the interactions of Escherichia coli lytic transglycosylase Slt35 with peptidoglycan, BIOCHEM, 39(8), 2000, pp. 1924-1934
Citations number
39
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMISTRY
ISSN journal
00062960 → ACNP
Volume
39
Issue
8
Year of publication
2000
Pages
1924 - 1934
Database
ISI
SICI code
0006-2960(20000229)39:8<1924:CSOTIO>2.0.ZU;2-X
Abstract
Lyric transglycosylases catalyze the cleavage of the beta-1,4-glycosidic bo nd between N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) i n peptidoglycan with concomitant formation of a 1,6-anhydro bond in the Mur NAc residue. To understand the reaction mechanism of Escherichia coli lytic transglycosylase Slt35, three crystal structures have been determined of S lt35 in complex with two different peptidoglycan fragments and with the lyr ic transglycosylase inhibitor bulgecin A. The complexes define four sugar-b inding subsites (-2, -1, +1, and +2) and two peptide-binding sites in a lar ge cleft close to Glu162. The Glu162 side chain is between the -1 and +1 su gar-binding sites, in agreement with a function as catalytic acid/base. The complexes suggest additional contributions to catalysis from Ser216 and As n339, residues which are conserved among the MltB/Slt35 lytic transglycosyl ases.