Structure and function of Frankia vesicles in dinitrogen fixation by actinorhizal plants. Final report, April 1, 1982-March 31, 1984

Technical Report · Fri Nov 01 04:00:00 EST 1985

OSTI ID:6381602

Torrey, J G

Frankia, a filamentous bacterium which induces N/sub 2/-fixing root nodules on the roots of a wide range of woody dicotyledonous plants, is the first known actinomycete which fixes dinitrogen when growing in free-living culture. The nitrogenase enzyme is induced in many strains of this organism by withholding fixed nitrogen compounds from its nutrient medium. Terminal swellings of the bacterial filaments develop rapidly and acetylene reduction activity (= nitrogenase) increases in proportion to the number of terminal vesicles formed. The induction of vesicles and establishment of acetylene reduction occurs under aerobic conditions, and the evidence is accumulating which demonstrates the existence of a multilaminate vesicle envelope which serves as a physical barrier protecting the oxygen-labile nitrogenase from denaturation. Our studies are concerned with the physiology, biochemistry and structural development of the N/sub 2/-fixing apparatus in Frankia grown in vitro and in root nodules of host plants. Diverse strains of Frankia are under study isolated and cultured from different host plants. Two strains have been studied, especially HFPArI3, an isolate from nodules of the red alder Alnus rubra, and HFPCcI3, isolated from root nodules of the tropical tree Casuarina cunninghamiana. The goal is to understand the structure and function which leads to optimum effectiveness for dinitrogen fixation. 9 refs.

• Research Organization: Harvard Univ., Petersham, MA (USA)
• DOE Contract Number: AC02-82ER12036
• OSTI ID: 6381602
• Report Number(s): DOE/ER/12036-2; ON: DE86005117
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
140504 -- Solar Energy Conversion-- Biomass Production & Conversion-- (-1989)
550200* -- Biochemistry
553000 -- Agriculture & Food Technology
59 BASIC BIOLOGICAL SCIENCES
60 APPLIED LIFE SCIENCES
ACTINOMYCES
AEROBIC CONDITIONS
BACTERIA
CELL CONSTITUENTS
CELL MEMBRANES
CULTURE MEDIA
ENZYME INDUCTION
ENZYMES
GENE REGULATION
LIPIDS
MEMBRANES
MICROORGANISMS
NITRO-GROUP DEHYDROGENASES
NITROGEN FIXATION
NITROGENASE
ORGANIC COMPOUNDS
ORGANOIDS
OXIDOREDUCTASES