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B6db references: 15975512

type Journal Article
authors Li, Y., Llewellyn, N.M., Giri, R., Huang, F. and Spencer, J.B.
title Biosynthesis of the unique amino acid side chain of butirosin: possible protective-group chemistry in an acyl carrier protein-mediated pathway.
journal Chem. Biol.
Activity 4.1.1.95
Family 4.1.1.95
sel selected
ui 15975512
year (2005)
volume 12
number 6
pages 665-75
 
abstract Butirosins A and B are naturally occurring aminoglycoside antibiotics that have a (2S)-4-amino-2-hydroxybutyrate (AHBA) side chain. Semisynthetic addition of AHBA to clinically valuable aminoglycoside antibiotics has been shown both to improve their pharmacological properties and to prevent their deactivation by a number of aminoglycoside-modifying enzymes involved in bacterial resistance. We report here that the biosynthesis of AHBA from L-glutamate, encoded within a previously identified butirosin biosynthetic gene cluster, proceeds via intermediates tethered to a specific acyl carrier protein (ACP). Five components of the pathway have been purified and characterized, including the ACP (BtrI), an ATP-dependent ligase (BtrJ), a pyridoxal phosphate-dependent decarboxylase (BtrK), and a two-component flavin-dependent monooxygenase system (BtrO and the previously unreported BtrV). The proposed biosynthetic pathway includes a gamma-glutamylation of an ACP-derived gamma-aminobutyrate intermediate, possibly a rare example of protective group chemistry in biosynthesis.
last changed 2014/02/21 15:02

B6db references