Acyl Intermediate (acyl + intermediate)

Distribution by Scientific Domains


Selected Abstracts


Structural modification of acyl carrier protein by butyryl group

PROTEIN SCIENCE, Issue 1 2009
Bai-Nan Wu
Abstract Fatty acid synthesis in bacteria is catalyzed by a set of individual enzymes known as the type II fatty acid synthase. Acyl carrier protein (ACP) shuttles the acyl intermediates between individual pathway enzymes. In this study, we determined the solution structures of three different forms of ACP, apo-ACP, ACP, and butyryl-ACP under identical experimental conditions. The structural studies revealed that attachment of butyryl acyl intermediate to ACP alters the conformation of ACP. This finding supports the more general notion that the attachment of different acyl intermediates alters the ACP structure to facilitate their recognition and turnover by the appropriate target enzymes. [source]


Structure of an aliphatic amidase from Geobacillus pallidus RAPc8

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 10 2007
Serah W. Kimani
The amidase from Geobacillus pallidus RAPc8, a moderate thermophile, is a member of the nitrilase superfamily and catalyzes the conversion of amides to the corresponding carboxylic acids and ammonia. It shows both amide-hydrolysis and acyl-transfer activities and also exhibits stereoselectivity for some enantiomeric substrates, thus making it a potentially important industrial catalyst. The crystal structure of G. pallidus RAPc8 amidase at a resolution of 1.9, was solved by molecular replacement from a crystal belonging to the primitive cubic space group P4232. G. pallidus RAPc8 amidase is homohexameric in solution and its monomers have the typical nitrilase-superfamily ,-,-,-, fold. Association in the hexamer preserves the eight-layered ,-,-,-,:,-,-,-, structure across an interface which is conserved in the known members of the superfamily. The extended carboxy-terminal tail contributes to this conserved interface by interlocking the monomers. Analysis of the small active site of the G. pallidus RAPc8 amidase suggests that access of a water molecule to the catalytic triad (Cys, Glu, Lys) side chains would be impeded by the formation of the acyl intermediate. It is proposed that another active-site residue, Glu142, the position of which is conserved in the homologues, acts as a general base to catalyse the hydrolysis of this intermediate. The small size of the substrate-binding pocket also explains the specificity of this enzyme for short aliphatic amides and its asymmetry explains its enantioselectivity. [source]


Structural modification of acyl carrier protein by butyryl group

PROTEIN SCIENCE, Issue 1 2009
Bai-Nan Wu
Abstract Fatty acid synthesis in bacteria is catalyzed by a set of individual enzymes known as the type II fatty acid synthase. Acyl carrier protein (ACP) shuttles the acyl intermediates between individual pathway enzymes. In this study, we determined the solution structures of three different forms of ACP, apo-ACP, ACP, and butyryl-ACP under identical experimental conditions. The structural studies revealed that attachment of butyryl acyl intermediate to ACP alters the conformation of ACP. This finding supports the more general notion that the attachment of different acyl intermediates alters the ACP structure to facilitate their recognition and turnover by the appropriate target enzymes. [source]