Nitrous oxide reduction in nodules: denitrification or N/sub 2/ fixation

Journal Article · Fri May 01 00:00:00 EDT 1987 · Appl. Environ. Microbiol.; (United States)

OSTI ID:6409348

Coyne, M S; Focht, D D

Detached cowpea nodules that contained a nitrous oxide reductase-positive (Nor/sup +/) rhizobium strain (8A55) and a nitrous oxide reductase-negative (Nor/sup -/) rhizobium strain (32H1) were incubated with 1% /sup 15/N/sub 2/O (95 atom% /sup 15/N) in the following three atmospheres: aerobic with C/sub 2/H/sub 2/ (10%), aerobic without C/sub 2/H/sub 2/, and anaerobic (argon atmosphere) without C/sub 2/H/sub 2/. The greatest production of /sup 15/N/sub 2/ occurred anaerobically with 8A55, yet very little was formed with 32H1. Although acetylene reduction activity was slightly higher with 32H1, about 10 times more /sup 15/N/sub 2/ was produced aerobically by 8A55 than by 32H1 in the absence of acetylene. The major reductive pathway of N/sub 2/O reduction by denitrifying rhizobium strain 8A55 is by nitrous oxide reductase rather than nitrogenase.

• Research Organization: Univ. of California, Riverside
• OSTI ID: 6409348
• Journal Information: Appl. Environ. Microbiol.; (United States), Vol. 53:5
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
NITROUS OXIDE
METABOLISM
OXIDOREDUCTASES
ENZYME ACTIVITY
PEAS
NITROGEN FIXATION
DENITRIFICATION
NITROGEN 15
RHIZOBIUM
TRACER TECHNIQUES
BACTERIA
CHALCOGENIDES
CHEMICAL REACTIONS
ENZYMES
FOOD
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MICROORGANISMS
NITROGEN COMPOUNDS
NITROGEN ISOTOPES
NITROGEN OXIDES
NUCLEI
ODD-EVEN NUCLEI
OXIDES
OXYGEN COMPOUNDS
PLANTS
STABLE ISOTOPES
VEGETABLES
550201* - Biochemistry- Tracer Techniques