Inhibition of nitrate and nitrite reduction by 2,4-dinitrophenol in ankistrodesmus

✍ Scribed by J. Ahmad; I. Morris

• Publisher: Springer
• Year: 1967
• Tongue: English
• Weight: 355 KB
• Volume: 56
• Category: Article
• ISSN: 0302-8933
• DOI: 10.1007/bf00408413

✦ Synopsis

The uncoupling agent, 2,4-dinitrophenol, inhibits the reduction of nitrite by the green alga Ankistrodesmus braunii but does not appear to prevent the reduction of nitrate (K~SSLm~, 1955;1959). This latter conclusion was based on the observation that nitrite accumulates in the medium when the alga is incubated with nitrate and dinitrophenol.

Preliminary observations from this laboratory (MoRRIs, unpublished) suggested that the uncoupling agent inhibits the utilization of both nitrate and nitrite by another green alga, ChIorella ~yrenoidosa. This apparent difference between two similar organisms initiated a detailed re-examination of the effect of dinitrophenol on nitrate and nitrite reduction by Ankistrodesmus. By measuring the disappearance of nitrate from the medium, 2,4-dinitrophenol can be seen to inhibit the assimilation of nitrate as well as that of nitrite. However, inhibition of nitrate utilization is less than 100~ and is dependent on the concentration of nitrate.