The effect of heat shock on the formaldehyde cycle in germinating acorns of European Turkey oak.
The effect of heat shock (40 degrees C) on the formaldehyde cycle has been studied in European Turkey oak (Quercus cerris L.) acorns germinated to a 10% increase in mass. Hydroxy-methyl groups bonded to sulfur, oxygen and nitrogen atoms were made to react with dimedone and the derivative obtained (formaldemethone), which represented the endogenous formaldehyde level, was determined by high performance liquid chromatography. Qualitative alterations of methyl donors and acceptors in the response of acorns to the heat shock have been mapped by MALDI (matrix assisted laser desorption ionization) mass analysis. In the first experiment the acorns were prevented from withering by wrapping them in aluminium foil and in the second they were not. The relatively high temperature of the acorns wrapped in aluminium foil was the dominant stress effect and the role of withering was subsidiary. Alteration of the endogenous formaldehyde level in the seed-leaves reflected the phases of the stress syndrome. If the withering were not hindered, two local minima in the alteration of endogenous formaldehyde level were found. First, the increase in temperature decreased the endogenous formaldehyde level and after a local maximum a repeated local minimum was observed as a delayed response. It is presumed that the second minimum was induced by the decreasing water amount becoming more and more significant in the seed-leaves.
Albert
L
L
Institute for Chemistry, University of Sopron, Hungary.
Németh
Z I
ZI
Varga
S
S
D002851:Chromatography, High Pressure Liquid; D005557:Formaldehyde / Q000378:metabolism*; D018869:Heat-Shock Response; D012639:Seeds; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013056:Spectrophotometry, Ultraviolet; D014197:Trees / Q000196:embryology*
D005557:Formaldehyde