Note on nitrate reduction inRhizobium

Abstract
Nitrate reduction in Rhizobium was previously shown to be so diverse that in addition to assimilatory reduction, it includes dissimilatory as well as defective reduction of nitrate (1–5). Little attention seems, however, to have been given to these early results, presumably because they were published in Japanese. Such a situation explains the recent appearance of the paper entitled “Denitrification in Rhizobium” (6). Denitrification by a nitrogen fixer such as Spirillum has also recently been reported (7–9).