NITROUS-OXIDE REDUCTASE (NOSZ) GENE-SPECIFIC PCR PRIMERS FOR DETECTION OF DENITRIFIERS AND 3 NOSZ GENES FROM MARINE-SEDIMENTS

Two PCR primer sets for the nitrous oxide reductase gene (nosZ) were d eveloped. The initial primers were based on three sequences in GenBank and used to amplify nosZ from continental shelf sediments and from tw o denitrifiers in culture, Thiosphaera pantotropha and Pseudomonas den itrificans. Three unique marine sediment nosZ genes were identified an d sequenced. The marine nosZ genes were most closely related to the no sZ genes of Paracoccus denitrificans or to Rhizobium meliloti. Alignme nt of all nosZ sequences currently available (n = 10) facilitated rede sign of the PCR primers. Three new primer sets which amplify 1100 bp, 900 bp and 250 bp regions of the nosZ gene were designed and tested. T he new primers robustly amplified nosZ fragments from samples in which the initial nosZ primers were only marginally successful. (C) 1998 Fe deration of European Microbiological Societies. Published by Elsevier Science B.V.