A- glycyl

Benzylsuccinate synthase has an amino acid sequence homologous to that of pyruvate formate lyase (p. 799 -801), contains a glycyl radical, and is activated in a manner similar to activation of pyruvate formate lyase. Propose a mechanism for formation of benzylsuccinate. See Krieger et al.383... 

FlO. 19. Energy contours for a glycyl residue. The units of energy are keal mole-1. The symbols R and L indicate the locations of the standard right- and left-handed a-helical conformations (Scott and Scheraga, 1966c). 

Logan, D. T., Andersson, J., Sj berg, B.-M., and Nordlund, P., 1999, A glycyl radical site in the crystal structure of a class III ribonucleotide reductase. Science 283 1499nl504. 

Recently, a glycerol dehydratase was discovered in the anaerobic bacterium Clostridium butyricum, whose active site contains a glycyl radical formed by the action of the 5 -deoxyadenosyl radical on a specific glycine residue of the protein (20). The 5 -deoxyadenosyl radical is generated not from coenzyme Bi2, but by one-electron reduction of the stmcturally much simpler molecule 5-adenosylmethionine (SAM), named poor man s B12 by Barker. Hence, this glycerol dehydratase performs the same reaction, probably with a similar pathway, to the coenzyme B 12-dependent glycerol dehydratase. 

The e-lysine tripeptide was isolated from bovine achilles tendon after its partial hydrolysis in 7 M HCl. It was identihed very thoroughly by both degradative and synthetic studies as L,L-A -(glycyl-a-glutamyl)-lysine... 

In 1968 Schroeder and co-workers (S22) described the presence of two types of y chains in the normal human newborn which are the products of nonallelic structural genes (see Section 5). These two types of y chains are termed °y and y chains because position 136 is occupied by a glycyl residue in the °y chain and by an alanyl residue in the chain. Several y chain variants have been described. The structural... 

The presence of a glycyl and an alanyl residue in position 136 indicates two peptides, and thus two y chains the chain with a glycyl residue in position 136 is termed the y chain and the one with an alanyl in this position the y chain. 

Among the numerous variations made to a-methyl-dopa, acylation with a glycyl-glycyl residue was claimed... 

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