Dear Helena, If you want we could maybe send you a plate of Pseudomonas Aureofaciens. We use them for both O and N isotopes of nitrate (see Kaiser et al, 2007, or Casciotti et al., 2002). It's rather similar to Chlororaphis, and in addition you also get O isotopes right because of reduced O atom exchange with the surrounding medium during the incubation. Please let me know if you want us to prepare a plate for you, and how would like to arrange for the shipping. Best regards, Samuel Morin LGGE, Grenoble, France On Apr 23, 2008, at 11:01 AM, Helena Jäntti wrote: > Does anyone where I could get the bacterial strain of Pseudomonas > chlororaphis that lacks the N2O reductase capacity? The ATCC # is > 43928 but is not currently available from ATCC. Alternatively, does > anyone know are there any other strains that could be used in the > "denitrifier"-method that is used in 15NO3 analyzes? > > Best regards, > > Helena Jäntti > > > Helena Jäntti (Msc) > Researcher > University of Helsinki/Division of Aquatic Sciences > >