• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.15-20
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• 2002

Diacylglycerol kinase (DGK) phosphorylates the second messenger diacylglycerol (DAG) to phosphatidic acid and it may play a role in signal transduction in Escherichia coli as well as in eukaryotic cells. In addition, DGK is important for microorganisms to adapt to several physiological stimuli. In Bacillus subtilis, the effect of stress on dgk transcription was examined by northern hybridization. The high level of dgk transcription was induced against high osmolarity, low pH value and low temperature. Transcriptional analysis revealed that the dgk gene and dgk upstream locus (ORF2, ORF3 and ORF4) were transcribed as a polycistronic mRNA to form an approximately 2.5 kb transcript.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.31-44
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• 1980

Climacteric phenomon in fruits was delayed ten days on the sub-atmospheric treatment than the normal atmospheric one. Average lipid content in tomatoes sampled was composed of neutral lipid (49%), phospholipid(31%) and glycolipid (13%). Seven constituents each from neutral and phospholipid were seperated through thin-lyaer chromatography. Changes on lipid content during treatments were associated with the climacteric pattern and the advance of maturity; At the climacteric on-set, the fruit color was light pink, and the content of neutral lipid was reduced to minimum. After this stage, this content was reversely increased. The maturity was related with diglyceride and sterol ester in neutral lipid, and phosphatidyl choline and phosphatidyl ethanolamine in phospholipid. The changes of two constituents each on both neutral and phospholipid were reversed each other. It was concluded that changes of lipid content in tomato fruits were closely associated with the advance of fruit maturity and climacteric pattern.