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Tang Lei , Stith Linda , Jaffe Eileen K
Substrate-induced interconversion of protein quaternary structure isoforms
Journal of Biological Chemistry. 2005 ;280(16) :15786-15793
PMID: AN 2005:333120   
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Abstract
The authors previously showed that human porphobilinogen synthase (PBGS) could exist in 2 dramatically different quaternary structure isoforms, which were proposed to be in dynamic equil. The quaternary structure isoforms of PBGS result from 2 alternative conformations of the monomer; one monomeric structure assembles into a high activity octamer, whereas the other monomeric structure assembles into a low activity hexamer. The kinetic behavior of these oligomers led to the hypothesis that turnover facilitates the interconversion of the oligomeric structures. The current work demonstrates that the interactions of ligands at the enzyme active site promote the structural interconversion between human PBGS quaternary structure isoforms, favoring the formation of the octamer. This observation illustrates that the assembly and disassembly of oligomeric proteins can be facilitated by protein motions that accompany enzymic catalysis. [on SciFinder (R)]
Notes
CAN 142:388233 7-5 Enzymes Fox Chase Cancer Center,Philadelphia,PA,USA. Journal 0021-9258 written in English. 106-60-5 (5-Aminolevulinic acid) Role: BSU (Biological study, unclassified), BIOL (Biological study) (substrate-induced interconversion of wild-type and F12L mutant human porphobilinogen synthase quaternary structure isoforms); 9036-37-7 (Porphobilinogen synthase) Role: BSU (Biological study, unclassified), PEP (Physical, engineering or chemical process), PRP (Properties), PYP (Physical process), BIOL (Biological study), PROC (Process) (substrate-induced interconversion of wild-type and F12L mutant human porphobilinogen synthase quaternary structure isoforms)