Nitrogen Fixation: Nitrogenase and Chemical Modelling

Synopsis

Concentrates on a suggested model for the operations of the two proteins of the nitrogenese enzyme which bacteria use to fix nitrogen. First shows how root modules of legumes possess nitrogen fixing bacteria, then how a bacterium is cultured and how proteins are extracted from it. There is a model for the nitrogenase operation, and a schematic illustration of the Chatt cycle for the nitrogen fixing process. This relates each step in the cycle to the progressive bonding of protons to a dinitrogen molecule, bound presumably at molybdenum, in the active site of the molybdo-protein. Dr Chris Pickett of the University of Sussex demonstrates his electrolytic cell which physically illustrates parts of the Chatt cycle, at room temperature and pressure. He adds a tungsten complex containing dinitrogen to the cathode compartment of the cell, into which dinitrogen is bubbling. By adding a source of protons (tosylic acid) he forms a hydrazine.

Series

S343 Videocassette 2

Language

English

Country

Great Britain

Medium

Video; Videocassette. Standard formats. col. 24 min.

Year of production

1990

Availability

Sale

Subjects

Agriculture; Chemistry

Keywords

inorganic chemistry; legumes; nitrogen fixation; root nodules

Credits

Producer

Michael Peet

Cast

Crawford Logan

Production Company

Name

BBC Open University Productions

Distributor

Name

Open University Worldwide

Web

http://www.ouw.co.uk External site opens in new window

Phone

+44 (0) 1908 274066

Address

Walton Hall
Milton Keynes
MK7 6AA

Notes

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