Adenosine bisphosphate

Acyl CoA s, such as acetyl CoA, are the most common thioesters in nature. Coenzyme A, abbreviated CoA, is a thiol formed by a phosphoric anhydride linkage (0 = P—O—P=0) between phosphopantetheine and adenosine 3, 5 -bisphosphate. (The prefix "bis" means "two" and indicates that adenosine 3, 5 -bisphosphate has two phosphate groups, one on C3 and one on C5. ) Reaction of coenzyme A with an acyl phosphate or acyl adenylate... 

The sulfotransferases catalyze formation of sulfate esters of compounds having hydroxy or amino groups. The donor in this transfer of a sulfuryl group is 3 -phosphoadenylsulfate, also named previously as 3 -phosphoadenosine-5 -phos-phosulfate (PAPS). An example of this reaction is seen in Eq. (11) for phenol as the sulfuryl (S03) acceptor, with the products of the reaction being phenyl sulfate and adenosine 3, 5 -bisphosphate (PAP). 

This enzyme [EC 2.S.2.2], also referred to as hydroxyste-roid sulfotransferase, catalyzes the reaction of 3 -phos-phoadenylylsulfate with an alcohol to produce adenosine 3, 5 -bisphosphate and an alkyl sulfate. The alcohols that can act as substrates include ahphatic alcohols, ascorbate, chloramphenicol, ephedrine, hydroxysteroids, and other primary and secondary alcohols. However, phenolic steroids will not serve as substrates (such alcohols can be acted upon by steroid sulfotransferases). 

This enzyme [EC 2.8.2.6] catalyzes the reaction of 3 -phosphoadenylylsulfate with choline to produce adenosine 3, 5 -bisphosphate and choline sulfate. 

This enzyme [EC 2.8.2.5] catalyzes the reaction of chon-droitin with 3 -phosphoadenylylsulfate to produce adenosine 3, 5 -bisphosphate and chondroitin 4 -suffate. Specifically, the sulfation is at the 4-position of A-acetyl-galactosamine residues of chondroitin. This enzyme is distinct from that of chondroitin 6-sulfotransferase [EC 2.8.2.17]. 

This manganese-dependent enzyme [EC S.6.2.2], also known as phosphoadenylylsulfatase, catalyzes the hydrolysis of 3 -phosphoadenylyl sulfate to yield adenosine 3, 5 -bisphosphate and sulfate. 

In Renilla the coelenterazine is stored as a coelenterazine sulfate, possibly having the structure shown. To convert this storage form to the active luciferin the sulfo group is transferred onto adenosine 3, 5 -bisphosphate to form 3 -phosphoadenosine 5 -phosphosulfate, the reverse of step d of Eq. 17-38. Tire luciferin of the ostracod crustacean Vargula hilgendorfii has a structure (Fig. 23-51) close to that from Renilla. 

Coenzyme A (CoA), biotin, and pyridoxal phosphate are also activation-transfer coenzymes synthesized from vitamins. CoA (CoASH), which is synthesized from the vitamin pantothenate, contains an adenosine 3, 5 -bisphosphate which binds reversibly, but tightly, to a site on an enzyme (Fig. 8.12A). Its functional group, a sulfhydryl group at the other end of the molecule, is a nucleophile that always... 

Adenosine-3, 5 -bisphosphate 3 -phosphohydrolase] (3.1.3.7) is produced. [Also acts on 3 -phospho-adenylylsulphate.]... 

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