The purification and properties of nucleoside phosphotransferase from mucosa of chicken intestine

Risultato della ricerca: Articlepeer review

6 Citazioni (Scopus)

Abstract

(1) Nucleoside phosphotransferase (nucleotide:3′-deoxynucleoside 5′-phosphotransferase, EC 2.7.1.77) has been purified from chicken intestine mucosa to apparent homogeneity. The enzyme is represented by a multisubunit protein at different degrees of association. It can dissociate into a compoenent with a marked fall in catalytic activity. (2) The associated forms are similar to the enzyme previously purified from chick embryo as regards: substrate specificity both with respect to nucleoside monophosphate donors and to deoxyribonucleoside acceptors; sigmoidicity in the rate curve with a variable phosphate donor; instability to heat, dilution and lowering of pH; the activating and protecting effect of nucleotides, particularly the diphosphate forms. The dissociated form displays lover Vmax and higher S0.5 than the associated ones; and the Hill constants are always about 1. With this form, nucleotides show only a modest activating effect and do not protect. (3) Mg2+, Mn2+ or Co2+ are required for catalytic activity, whereas the protective effect of nucleotides is independent of divalent metals. (4) Inorganic phosphate stabilizes associated forms of the enzyme, but inhibits its activity by competing with nucleotide effectors. (5) The enzyme behaves also as a phosphohydrolase, particularly with respect to deoxyribonucleoside monophosphates; deoxyuridine and deoxythymidine inhibit hydrolytic activity.
Lingua originaleEnglish
pagine (da-a)231-244
Numero di pagine14
RivistaBIOCHIMICA ET BIOPHYSICA ACTA
Volume786
Stato di pubblicazionePublished - 1984

All Science Journal Classification (ASJC) codes

  • Biophysics
  • Structural Biology
  • Biochemistry
  • Molecular Biology

Fingerprint Entra nei temi di ricerca di 'The purification and properties of nucleoside phosphotransferase from mucosa of chicken intestine'. Insieme formano una fingerprint unica.

Cita questo