%0 Journal Article %A Nagahama, Kazuhiro %A Ogawa, Takahira %A Fujii, Takao %A Tazaki, Masato %A Goto, Masao %A Fukuda, Hideo %T l-Arginine is essential for the formation in vitro of ethylene by an extract of Pseudomonas syringae %D 1991 %J Microbiology, %V 137 %N 7 %P 1641-1646 %@ 1465-2080 %R https://doi.org/10.1099/00221287-137-7-1641 %I Microbiology Society, %X Summary: A system was developed for the formation of ethylene in vitro by an extract of Pseudomonas syringae pv. phaseolicola PK2. The ethylene-forming activity of a cell-free extract of this bacterium measured in a system reported previously was almost completely lost when the cell-free extract was dialysed against potassium phosphate buffer for 24 h at 4 °C. When the fraction of cell-free extract with a molecular mass < 10 kDa (SupI) was added back to the enzyme fraction after gel filtration of the cell-free extract, the enzymic activity increased to about four times that of the gel-filtered crude enzyme. The action of SupI could be reproduced by the addition of l-arginine. The complete system for the formation of ethylene under aerobic conditions in vitro required 0·25 mm-2-oxoglutarate, 0·2 mm-FeSO4, 2 mm-DTT, 10 mm-l-histidine and 0·2 mm-l-arginine. The cofactor specificity was examined by replacing l-arginine or l-histidine with various analogues, but none of them were effective. The components of this system, with the exception of l-histidine, were similar to those of a system derived from the ethylene-producing, plant pathogenic fungus Penicillium digitatum which also produced ethylene in vitro in a reaction dependent on 2-oxoglutarate. The intermediates in the ethylene-forming reaction are postulated and the roles of l-arginine and l-histidine in the formation of ethylene by Ps. syringae are discussed. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-137-7-1641