Comparative Enzymology of the Adenosine Triphosphate Sulfurylases from Leaf and Swollen Hypocotyl Tissue of Beta vulgaris: Multiple Enzyme Forms in Hypocotyl Tissue 1
AUTOR(ES)
Paynter, D. I.
RESUMO
ATP sulfurylase activity was partially purified from the swollen hypocotyl of beetroot (Beta vulgaris); activity was measured by sulfate-dependent PPi-ATP exchange. The ATP sulfurylase activity was separated from pyrophosphatase and ATPase activities which interfere with the assay of ATP sulfurylase activity. The ATP sulfurylase activity from hypocotyl tissue was invariably resolved into two approximately equal activities (hypocotyls I and II) by ion exchange chromatography and polyacrylamide gradient gel electrophoresis. Both enzymes catalyzed selenate- and sulfate-dependent PPi-ATP exchange; the affinity of hypocotyl II for these substrates was greater than for hypocotyl I. It is unlikely that the two activities arise by allelic variation or as an artifact of purification; they are most probably isoenzymes. Studies of the subcellular localization of the two hypocotyl enzymes were inconclusive.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=541361Documentos Relacionados
- Acne vulgaris: prevalence and clinical forms in adolescents from São Paulo, Brazil
- Enzymatic Degradation of Adenosine Triphosphate to Adenine by Cabbage Leaf Preparations. 1
- Salt accumulation and adenosine triphosphate in carrot xylem tissue.
- Isolation of Vacuoles from Root Storage Tissue of Beta vulgaris L. 1
- In Vivo Nitrite Reduction in Leaf Tissue of Phaseolus vulgaris L. 1
