VOPROSY MEDITSINSKOI KHIMII (ISSN 0042-8809)

Role of the sulfhydryl group in the thiamine pyrophosphokinase activity of the rat liver

   
Artsukevich I.M., Voskoboev A.I., Ostrovskiĭ I.M.
PubMed Id: 6331000
Year: 1984  Volume: 30  Issue: 2  Pages: 108-112
Amount and reactivity of SH-groups in thiamine pyrophosphokinase from rat liver tissue were studied using the mercaptide-forming reagents HgCl2 and p-chloromercury-benzoate (pCMB). Two types of SH-groups were found: the first--readily accessible and the second--partially concealed groups. Amount of these groups altered in presence of 8 M urea and 0.5% sodium dodecylsulfate. The enzymatic activity was inhibited by 30% after pCMB modification of the first type SH-groups and by 100% if second type SH-groups were blocked. All the substrates used, except of ATP, protected partially thiamine pyrophosphokinase against the inactivating effect of the reagent. The mercaptide-forming reagents exhibited dissimilar efficiency apparently due to different nature of the chemical bonds formed: pCMB developed the bond protein-S-HgR and HgCl2 formed--(protein-S)2Hg bond. The data obtained suggest that the SH-groups are localized close to the active site of thiamine pyrophosphokinase and that they participate in stabilization of the molecular structure of the enzyme.
Download PDF:
Citation:

Artsukevich, I. M., Voskoboev, A. I., Ostrovskiĭ, I. M. (1984). Role of the sulfhydryl group in the thiamine pyrophosphokinase activity of the rat liver. Voprosy meditsinskoi khimii, 30(2), 108-112.
References
 1984 (vol 30)
 1983 (vol 29)
 1982 (vol 28)
 1981 (vol 27)
 1980 (vol 26)
 1979 (vol 25)
 1978 (vol 24)
 1977 (vol 23)
 1976 (vol 22)
 1975 (vol 21)
 1974 (vol 20)
 1973 (vol 19)
 1972 (vol 18)
 1971 (vol 17)
 1970 (vol 16)
 1969 (vol 15)
 1968 (vol 14)
 1967 (vol 13)
 1966 (vol 12)
 1965 (vol 11)