We have been using both Pseudomonas aureofaciens and P. chlororaphis (or subspecies, whatever the current taxonomy is) for bacterial denitrification of nitrate depending on if we want d18O or not, respectively, for years now. We have always had the existence of a blank with P. aureofaciens and not with P. chlororaphis despite using similar processing methods. P. chlororaphis seems to be more cooperative in general. I am emailing you to ask:
1) Do you find differences when using Pseudomonas aureofaciens vs P. chlororaphis (other than those attributed to fractionation with water)?
2) Do you have a blank for either species?
Department of Earth and Space Sciences
University of Washington
Seattle, WA 98195
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