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Trade publications; such as catalogs, technical bulletins, and web sites; are a valuable source of information for students in biotechnology-related courses. Not only do catalogs and technical publications provide current information, but they also contain a wealth of useful facts and physical constants that biologists need on-the-job. Further, using catalogs in the classroom mimics the way that science is carried out in the real world. In the research lab, scientists and technicians often rely on catalogs, technical bulletins, and web sites, for quick and useful information.

I probably wouldn’t ever have learned about inteins – self-splicing proteins – for example if I hadn’t seen the NEB newsletter sitting around in the coffee room.

I’m not sure if this practice is common now, but in the earlier days of molecular biology many of the reagent vendors, like NEB, Stratagene, and BRL, were actively engaged in research and in spreading the news of new discoveries.

Companies were also engaged in testing research protocols. In the late eighties, molecular biology students were very superstitious, possibly because we didn’t really know what we were doing anyway and each protocol had so many steps. As a consequence, we tended to follow protocols somewhat blindly, with few deviations. The protocols were gold and we rarely went “off-book.” Fortunately, BRL (a defunct reagent company) used to have a wonderful publication where they did experiments to test the pervasive myths of the molecular biology lab. If it weren’t for the scientists at BRL, biologists would probably still be precipitating DNA in dry ice baths and using storing oligos in buffers with the wrong pH.

I frequently used catalogs or technical bulletins from reagent vendors as teaching resources in biotechnology courses at Seattle Central Community College. All my students had their own copies of the New England BioLabs catalog. They used this catalog to find information on restriction enzymes, buffers, absorbance constants, molecular weights, and other facts that they needed for doing molecular biology lab work.

The other catalog that I found essential was the Difco Manual. For microbiologists, the Difco Manual is the equivalent of Harold McGee’s classic book for chefs (“On Food and Cooking”). For years, as a microbiologist, I used LB or BHI broth to grow bacteria and made media with all kinds of mysterious ingredients like tryptone and peptone . The Difco manual, with its wonderful descriptions of media ingredients, opened my eyes and provided enlightenment. Naturally, the Difco manual became required reading for students in our media and solution preparation course.

Fortunately, those two resources are available on line. You can get the NEB reference material at: www.neb.com and the Difco manual here. The Difco manual isn’t free but it is fun to read.

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  1. #1 iGollum
    July 27, 2006

    Umm… young microbiology grad student here, slightly superstitious about protocols (though starting to get comfortable with the idea of some moderate tweaking), and also regularly using LB and BHI, with tryptone and all that jazz, to grow my Bacilli… Never had a problem with the ‘established’ recipes, but would love to learn some new tricks, Anything in particular that you were enlightened about relative to media? Do spill, o learned one :-)

  2. #2 Sandra Porter
    July 27, 2006

    Ah, grasshopper, you wish to know about my handy dandy media making tricks.

    Media contents are fascinating, but the standard plate recipes – LB, miminal medium, and nutrient agar- all worked pretty well for me. I did spend quite a bit of time reading through the Difco manual when I was consulting for a local brewery and they wanted to make kosher beer. I think we settled on Potato dextrose agar, since we knew there wouldn’t be any peptone or tryptone from meat of unknown origin.

    My advice is to make media in batches and store it, autoclaved, in 500 ml bottles in the refrigerator. Then you can microwave a bottle, cool it to 55°C, and pour plates whenever you need them.

    I would also make my antibiotic solutions ahead of time in 1000X concentrations (so that I could be lazy and just add one microliter per ml of media). I would filter sterilze them and store them in 500 microliter aliquots at -70°C, so that I could thaw them quickly whenever I needed to make a batch of plates.

  3. #3 iGollum
    August 1, 2006

    Oh, sensei, you honor me by taking time to answer, I am so grateful :-)

    Store bottles of medium and microwave them to pour as needed? Doh, I don’t know why I never thought of that. When I think of all the times I’ve been at the lab on weekends and couldn’t make the plates I needed because we’re not allowed to use the pressure cookers when there’s no one else around… Thanks for the tip! It’ll definitely come in handy.

    I keep my antibiotics in 1000X as well; I figure it’s not laziness, it’s being efficient (and that way it’s less likely I’ll mess up the concentration – I abhor dilution calculations).

    There’s just one I have trouble with, Rifampicin. Have you ever had to deal with that one? It’s horrid. Have to solubilize it in methanol to get a decent concentration, and even so all it ever does is try to precipitate as soon as you turn around. And it makes little red flecks upon contact with the medium. Easy to spot the Rif plates among the rest, though, as they tend to be quite orangey.

    Not sure I’ll ever need the recipe for kosher beer, but if I ever do at least I’ll know who to ask :-D