DH5α strains and a PSA to sequence your plasmids

[@thebumblingbiochemist]

There are other mutations too, gyrA96, which gives it nalidixic acid resistance; thi-1 which makes it a thiamine auxotroph (can’t make its own thiamine); Δ(lacZYA-argF)U169 - a deletion that leads to increased hydrogen peroxide resistance; and others It’s not that we need *all* of these mutation, but as long as they don’t get in the way, we’ll let them stay! And, after all the mutagenesis these cells have gone through, there are tons more that just haven’t shown to be “interesting” yet - but a lot of mutations are only discovered under conditions when that protein’s needed - like, you wouldn’t know that there’s a mutation in the thiamine metabolism gene if you always grew them with plenty of thiamine. So a lot of the “new” mutations scientists discover have likely been there (or something close) for quite a while. All this is housed in a single, circular chromosome with ~4.6million DNA letters & ~4 and a half thousand genes. for more info: addgene Plasmids 101: Common Lab E. coli Strains, Matthew Ference, 2014: blog.addgene.org/plasmids-101-common-lab-e-coli-strains DH5α strain info on the CGSC (Coli Genetic Stock Center) website: cgsc.biology.yale.edu/Strain.php?ID=150015 Open WetWare E. coli genotypes Wiki: openwetware.org/wiki/E._coli_genotypes#DH5%CE%B1 Genetic backgrounds of each Escherichia coli strain used in The ST2OOL Project, 2014 iGem: 2014.igem.org/wiki/images/5/58/Genetic_backgrounds_of_each_Escherichia_coli_strain_used_in_The_ST2OOL_Project.pdf the RelA1 mutation: Shokri, A., Veide, A. & Larsson, G. RelA1 gene control of Escherichia coli lipid structure and cell performance during glucose limited fed-batch conditions. Appl Microbiol Biotechnol 73, 464-473 (2006). doi.org/10.1007/s00253-006-0480-9 the door mutation: Gene Cloning and Manipulation - Page 61, Christopher Howe, 2007 books.google.com/books?id=OWXM4Q3-ieEC&pg=PA61&lpg=PA61&dq=deor+mutation&source=bl&ots=xtwaKleNQ-&sig=ACfU3U0K9_6ZQv_of8dR5jFD6D6CQjgjgg&hl=en&sa=X&ved=2ahUKEwj2uui-5uf3AhWWFjQIHVThC5IQ6AF6BAgZEAM Doug Hanahan biography, DNA Learning center: dnalc.cshl.edu/view/16722-Biography-34-Doug-Hanahan-1951-.html past posts on related topics: more on BL-21 & other expression strains: bit.ly/bl21_rare_codons more on transformation: bit.ly/transformheatshock more on blue-white screening: bit.ly/bluewhitescreening more on DNA sequencing: bit.ly/DNAsequencingmethods & bit.ly/sequenceclones & bit.ly/sequencetermstools     more about all sorts of things: #365DaysOfScience All (with topics listed) 👉 bit.ly/2OllAB0 or search blog: thebumblingbiochemist.com