Incorporation of atmospheric oxygen into the carbonyl functionality of the protochlorophyllide isocyclic ring.

نویسندگان

  • C J Walker
  • K E Mansfield
  • K M Smith
  • P A Castelfranco
چکیده

Detached cucumber (Cucumis sativus L. var. Beit Alpha) cotyledons incubated in darkness with 5-aminolaevulinic acid and either 16O2 air (control) or 18O2 in N2 accumulated protochlorophyllide. This was converted into methyl phaeoporphyrin alpha 5 and analysed by mass spectrometry. The molecular ion of the methyl phaeoporphyrin alpha 5 derived from the 18O2 incubation was 2 mass units greater than that of the control, establishing that the oxo oxygen atom of the isocyclic ring is derived from atmospheric oxygen.

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عنوان ژورنال:
  • The Biochemical journal

دوره 257 2  شماره 

صفحات  -

تاریخ انتشار 1989