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Title: Measurement of CA1P and CA in leaves

Abstract

Carboxyarabinitol-1-phosphate (CA1P) and carboxyarabinitol (CA) were assayed in leaves by isotope dilution. {sup 14}C-labeled standards were synthesized from (2-{sup 14}C) CABP using acid (CA1P) or alkaline (CA) phosphatase. Either was added to boiling 80% EtOH along with liquid N{sub 2}-killed leaves. Each was largely purified by anion exchange chromatography. CA1P samples were subjected to 2D-TLE/TLC. The specific activity of the {sup 14}C-containing spot was measured using alkaline phosphatase. CA samples were run on an HPLC and the specific activity was determined using a UV monitor and a flow-through radioisotope detector. In 3 of the tested species, light/dark amount of CA1P (nmol/mg Chl) were kidney bean, 0.7/67; sugar beet, 0.8/33; and Alocasia, 0/3.4. Light/dark CA levels (nmol/mg Chl) in these respective species were 897/653, 3.2/3.5, and 5.7/4.6. These results support the hypothesis that CA is a product of CA1P metabolism in vivo under high light, but also indicate that CA is not the only intermediate involved in CA1P synthesis under low light/dark conditions.

Authors:
; ;  [1]
  1. (Univ. of Nevada, Reno (USA))
Publication Date:
OSTI Identifier:
5851111
Report Number(s):
CONF-9007196--
Journal ID: ISSN 0079-2241; CODEN: PPYSA
Resource Type:
Conference
Resource Relation:
Journal Name: Plant Physiology, Supplement; (USA); Journal Volume: 93:1; Conference: Annual meeting of the American Society of Plant Physiologists, Indianapolis, IN (USA), 29 Jul - 2 Aug 1990
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 54 ENVIRONMENTAL SCIENCES; VISIBLE RADIATION; BIOLOGICAL EFFECTS; ALCOHOLS; CARBON 14 COMPOUNDS; LEAVES; PHOSPHORUS COMPOUNDS; TRACER TECHNIQUES; ELECTROMAGNETIC RADIATION; HYDROXY COMPOUNDS; ISOTOPE APPLICATIONS; LABELLED COMPOUNDS; ORGANIC COMPOUNDS; RADIATIONS 550201* -- Biochemistry-- Tracer Techniques; 540110

Citation Formats

Moore, B.d., Kobza, J., and Seemann, J.R. Measurement of CA1P and CA in leaves. United States: N. p., 1990. Web.
Moore, B.d., Kobza, J., & Seemann, J.R. Measurement of CA1P and CA in leaves. United States.
Moore, B.d., Kobza, J., and Seemann, J.R. 1990. "Measurement of CA1P and CA in leaves". United States. doi:.
@article{osti_5851111,
title = {Measurement of CA1P and CA in leaves},
author = {Moore, B.d. and Kobza, J. and Seemann, J.R.},
abstractNote = {Carboxyarabinitol-1-phosphate (CA1P) and carboxyarabinitol (CA) were assayed in leaves by isotope dilution. {sup 14}C-labeled standards were synthesized from (2-{sup 14}C) CABP using acid (CA1P) or alkaline (CA) phosphatase. Either was added to boiling 80% EtOH along with liquid N{sub 2}-killed leaves. Each was largely purified by anion exchange chromatography. CA1P samples were subjected to 2D-TLE/TLC. The specific activity of the {sup 14}C-containing spot was measured using alkaline phosphatase. CA samples were run on an HPLC and the specific activity was determined using a UV monitor and a flow-through radioisotope detector. In 3 of the tested species, light/dark amount of CA1P (nmol/mg Chl) were kidney bean, 0.7/67; sugar beet, 0.8/33; and Alocasia, 0/3.4. Light/dark CA levels (nmol/mg Chl) in these respective species were 897/653, 3.2/3.5, and 5.7/4.6. These results support the hypothesis that CA is a product of CA1P metabolism in vivo under high light, but also indicate that CA is not the only intermediate involved in CA1P synthesis under low light/dark conditions.},
doi = {},
journal = {Plant Physiology, Supplement; (USA)},
number = ,
volume = 93:1,
place = {United States},
year = 1990,
month = 5
}

Conference:
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