Water-Soluble Class C β-Lactamase Catalytic Residue Mimic: Effect of Proximally Positioned Functional Groups on their pKa Values
摘要:
Molecules mimicing class C beta-lactamase catalytic residues were synthesized to study the effect of proximal positioning of serine, lysine and tyrosine side chains on their pKa values. The three amino acid side chains were mimicked by hydroxymethyl group, alkyl ammonium group and phenol which were linked by a short skeleton to ensure interaction among these functionalities. Comparison of the mimics in water showed a phenolic pKa decrease of up to 3.6 units. The finding supports the possible role of tyrosine as a general acid/base catalyst in acylation of class C beta-lactamase. (C) 1997 Elsevier Science Ltd. All rights reserved.
A series of 9-methoxy- and 9-methyl-2,11-dithia[3.3]metacyclophanes are obtained by the coupling reaction of the corresponding 1,3-bis(bromomethyl)benzenes and bis(sulfanylmethyl)benzenes in ethanol under the high dilution conditions. The conformational studies of 2,11-dithia[3.3]metacyclophanes as well as the ring current interactions derived from benzene ring are also described.
Water-Soluble Class C β-Lactamase Catalytic Residue Mimic: Effect of Proximally Positioned Functional Groups on their pKa Values
作者:Yoko Kato-Toma、Seiichi Imajo、Masaji Ishiguro
DOI:10.1016/s0040-4039(97)10486-5
日期:1998.1
Molecules mimicing class C beta-lactamase catalytic residues were synthesized to study the effect of proximal positioning of serine, lysine and tyrosine side chains on their pKa values. The three amino acid side chains were mimicked by hydroxymethyl group, alkyl ammonium group and phenol which were linked by a short skeleton to ensure interaction among these functionalities. Comparison of the mimics in water showed a phenolic pKa decrease of up to 3.6 units. The finding supports the possible role of tyrosine as a general acid/base catalyst in acylation of class C beta-lactamase. (C) 1997 Elsevier Science Ltd. All rights reserved.