1F3X

S402P MUTANT OF RABBIT MUSCLE PYRUVATE KINASE

Summary for 1F3X

• Entry DOI: 10.2210/pdb1f3x/pdb
• Related: 1F3W 1PKN
• Descriptor: PYRUVATE KINASE, POTASSIUM ION, MANGANESE (II) ION, ... (5 entities in total)
• Functional Keywords: pyruvate kinase, s402p, muscle isozyme, transferase
• Biological source: Oryctolagus cuniculus (rabbit)
• Cellular location: Cytoplasm (By similarity): P11974
• Total number of polymer chains: 8
• Total formula weight: 465399.60

Authors

Wooll, J.O.,Friesen, R.H.E.,White, M.A.,Watowich, S.J.,Fox, R.O.,Lee, J.C.,Czerwinski, E.W. (deposition date: 2000-06-06, release date: 2001-10-03, Last modification date: 2023-11-15)

Primary citation

Wooll, J.O.,Friesen, R.H.,White, M.A.,Watowich, S.J.,Fox, R.O.,Lee, J.C.,Czerwinski, E.W.
Structural and functional linkages between subunit interfaces in mammalian pyruvate kinase.
J.Mol.Biol., 312:525-540, 2001

PubMed Abstract: Mammalian pyruvate kinase (PK) is a four-domain enzyme that is active as a homo-tetramer. Tissue-specific isozymes of PK exhibit distinct levels of allosteric regulation. PK expressed in muscle tissue (M1-PK) shows hyperbolic steady-state kinetics, whereas PK expressed in kidney tissue (M2-PK) displays sigmoidal kinetics. Rabbit M1 and M2-PK are isozymes whose sequences differ in only 22 out of 530 residues per subunit, and these changes are localized in an inter-subunit interface. Previous studies have shown that a single amino acid mutation to M1-PK at either the Y (S402P) or Z (T340 M) subunit interface can confer a level of allosteric regulation that is intermediate to M1-PK and M2-PK. In an effort to elucidate the roles of the inter-subunit interaction in signal transmission and the functional/structural connectivity between these interfaces, the S402P mutant of M1-PK was crystallized and its structure resolved to 2.8 A. Although the overall S402P M1-PK structure is nearly identical with the wild-type structure within experimental error, significant differences in the conformation of the backbone are found at the site of mutation along the Y interface. In addition, there is a significant change along the Z interface, namely, a loss of an inter-subunit salt-bridge between Asp177 of domain B and Arg341 of domain A of the opposing subunit. Concurrent with the loss of the salt-bridge is an increase in the degree of rotational flexibility of domain B that constitutes the active site. Comparison of previous PK structures shows a correlation between an increase in this domain movement with the loss of the Asp177: Arg341 salt-bridge. These results identify the structural linkages between the Y and Z interfaces in regulating the interconversion of conformational states of rabbit M1-PK.

PubMed: 11563914
DOI: 10.1006/jmbi.2001.4978

Experimental method

X-RAY DIFFRACTION (2.8 Å)