Hi Everyone! The area of microbiology/genomics is a bit foreign to me and I have run across a common theme in the naming of mutant bacterial strains I am reading about in the literature and I am hoping I can get help interpreting the notation. In numerous papers I have read recently I am seeing this notation where the author gives the name of a gene, two colons then the antibiotic resistance. For example, they have luxU::Kn^r (Kanamycin resistance). I have read through the materials and methods in each of these papers and it seems as if they are making these strains null for the gene that proceeds the two colons but I have never seen this two colon notation before (only one colon). Am I correct in my belief that this is the case (for example that in the case of my example that that notation indicates it is a luxU null strain)? It seems to read that way in certain places in the paper but being in such unfamiliar territory, I am still uncertain. Any help is greatly appreciated. Thanks!

Yes, that is correct. The "::" notation indicates an insertion into the gene, so luxU::Kn indicates a kanamycin cassette was inserted somewhere in the open reading frame to disrupt its expression.

Thank you very much! When I look at the paper again in the context of your explaination, it makes perfect sense.