Abstract:
This chapter provides a general introduction to phosphate monoester
hydrolysis, the stereochemistry and mechanism of the reaction and the use of metal
ions. It discusses several phosphatases with special emphasis on enzymes belonging
to the haloacid dehalogenase (HAD) superfamily, members of which are involved in
diverse metabolic processes in the cell. Features that form the basis of classifying
this superfamily into several subclasses are discussed. A brief survey of available
literature on HAD superfamily is also included. Further, the chapter elaborates on
5'-nucleotidases, their classification and importance in cellular metabolism. The
chapter concludes with an account on current understanding about HAD
superfamily members and 5'-nucleotidases. Legionella pneumophila IMP/GMP
specific cytosolic 5'-nucleotidase (cN-II), Plasmodium falciparum IMP-specific 5'-
nucleotidase (ISN1) and a broad specificity phosphatase from Plasmodium vivax,
all three being members of HAD superfamily, form the theme of studies reported in
this thesis.