21. Sulfation Linked to ATP Cleavage

摘要: Publisher Summary This chapter discusses sulfation linked to adenosine triphosphate (ATP) cleavage. The utilization of sulfate for ester formation and the reduction sulfite both require initial adenylylsulfate (APS) by enzyme, ATP-sulfurylase. ATP-Sulfurylase must be assumed widely distributed in nature because observations date indicate that all organisms capable reducing or forming esters possess this enzyme; however, even evidence type is scarce invertebrates. Four general assay systems have been utilized determination ATP-sulfurylase: first these methods based on observation ATP-sulfurylase catalyzes hydrolysis ATP AMP pyrophosphate presence specific Group VI anions. A second procedure involves measurement APS pyrophosphate. third method sulfate-dependent exchange radioactive PPi into ATP. It has employed mechanistic studies most recently crude plant extracts. last direct formation, which easily accomplished use sulfate. technique qualitatively demonstrate sulfate-activating system. In systems, only trace amounts are usually formed PAPS major nucleotide accumulating. generally inferred from PAPS, many instances reviewed Roy Trudinger.