Archive for the 'Science History' Category
I think I may be a nerd.
No, no, don’t try to deny it. I think it pretty much has to be true for someone who reads a 10-page scientific paper (hover or click here to see the reference) in order to learn that bacteria-snot is slimy. Yes, I am a nerd. And for that I am deeply, deeply….
Oh, who am I kidding? I like being a nerd.
For one thing, being a nerd allows me to fully enjoy one of the perks that my job gives me – namely access to a lot of scientific papers that I otherwise wouldn’t be able to afford to obtain access to from the greedy [insert your favority profanity here] who insist on charging $30 for permission to look at a decades-old articles for a day. I should add that this perk includes Inter-Library Loan for articles that I can’t get online, and the service on campus is great so far. Same day delivery of a classic article from 1930 in what I’m guessing most people would probably consider an obscure journal.
It doesn’t have quite the same thing in it that I expected from the source that pointed me to it, but I think it can still be considered “classic”. I need to re-read it more carefully to make a final decision on this, but I think I have my next “The Giant’s Shoulders” article in time for this month’s upcoming issue. And, yes, the picture attached to this post is a hint (and, no, it’s not directly related to the bacteria-snot article mentioned above in any way…)
Busy week with unpleasant surprises, but I ain’t dead yet. You’re probably wondering what a hot dog that’s apparently eagerly anticipating eating itself has to do with that. The answer is: nothing, but it does relate to something I have been intending to post about for a long time, but haven’t since I didn’t have access to the paper…
So, in lieu of blasting out Twitter®-style updates on my Laconica feed that nobody reads anyway (a few people no doubt see the echo of them on Twitter® itself, but I don’t know if anyone cares…), here are a couple of what-I’m-doing-now updates before I go to bed:
- I just shot off an email to the webmaster (the only contact I could find who might have the relevant information) of the Institute of Brewing and Distilling, trying to get access to a classic paper published in the Journal of the Institute of Brewing and Distilling for the upcoming “On the Shoulders of Giants” carnival.
There’s no way I can afford the ~$300US that it would cost to join the group, nor even at the moment to pay the typical $30 or so that greedy paywall-imprisoned publishers charge for individual articles. However, they appear to be opening up their archives to the public, for which I think they deserve substantial praise. Still, they haven’t worked their way back to the first few decades of the 20th century yet, so I had to email and ask if there was a way to get the article in question. If not, I’ll see if there’s any way to get it through inter-library loan in time.
- “Small Things Considered” asks “What Microbiological Discovery in 2008 Did You Find Especially Interesting?” Which brings us to the “self-eating” thing.
The paper on caffeine’s induction of macroautophagy (“self-eating”) in yeast (and what happens when benzoic acid is also present) finally escaped from the paywall prison in January, and I now have a copy. I at least thought it was full of interesting implications (along with some useful knowledge), so I’ll hopefully be posting about it soon.
- I’m also a computer nerd
Particularly when it comes to things like Linux. I’ve been thinking of trying to do some recordings on a couple of practical subjects that interest me for “Hacker Public Radio”
- And of course, I still need to do some Xanthomonas snot Xanthan Gum experiments.
an attention-whorewilling to listen to my readers’ interests, so if anyone has suggestions or comments feel free to post them…
Just a brief point first: President Obama in his inaugural address promised to “restore science to its rightful place.” In traditional fashion, this prompted all manner of verbosity on blogs around the web concerning just what science’s rightful place actually is. Let me just take a moment to settle this question:
Science’s rightful place is kneeling at my feet in supplication and doing my bidding! AH, HA HA HA HA HA!!!!!
But that’s not what I came here to post about. Instead, I wanted to mention a paper I finally got my hands on. You may recall that some time back there were a few stories that popped up about what was said to be a “you can’t get drunk on beer” paper published back in the 1950′s. As usual, the people doing the reporting couldn’t be bothered to actually cite the paper in question, but I figured out which one it was. The paper is this one:
Greenberg LA:”The Definition of an Intoxicating Beverage”; Q J Stud Alcohol. 1955 Jun;16(2):316-25.
I have that paper. And I am quite disappointed in it in much the same way I was with Linus Pauling’s paper proposing a triple-helix structure for DNA. I did, though, learn some interesting things from Greenberg’s paper.
It turns out that the paper actually concerns the legal definition of “intoxication” and whether or not, based on this definition, beer should be classified as an “intoxicating beverage”. Greenberg actually raises some good points…but first, some amusement:
“The average alcohol content of American beers is 3.7 per cent[...]The strongest ale is 4.2 per cent” (page 320, paragraph 4)
Unfortunately, this isn’t quite as funny as it sounds, because the part I clipped out of that quote is where he says “by weight”. It’s still kinda funny though, since that would mean, in mass-market-bladderwash terms, that “The Strongest Ale” is Heineken.
This Alcohol-by-Weight-vs-Volume issue may actually be part of why American beers have a reputation for having watery, feeble beers. It evidently used to be that places like Canada were using alcohol-by-volume, while the US was using alcohol-by-weight on their labels. An otherwise-identical beer bottled in Canada would have a higher “percent alcohol” on the label than the US-bottled version, making it seem as though the American version was weaker. So, evidently it’s not really true…things like “Coors Lite” notwithstanding. (See this recent page at Fermentarium.com for more details.)
But back to the point of the paper…evidently as Greenberg was writing this paper half a century ago, there wasn’t a clear, quantitative scientific or legal definition for “intoxication”. He points out that you can’t just define it in terms of alcohol merely having noticeable effects on the drinker, since the magnitude of the unpleasant effects at low to moderate drinking levels aren’t really much different than that for (for undesirable effects) lack of sleep, distraction [remember all those studies saying talking on the cell-phone while driving is as bad as being drunk?], hunger and so forth. For that matter, I think we can all see the problem of trying to arrest anyone who is being relaxed and amiable for “public intoxication”.
Greenberg solves this problem by looking at the average blood-alcohol concentration of people arrested for “intoxication” (0.21% back in the 1950′s, evidently), and a couple of previous studies from the 1920′s and 1930′s, and he finally settles on 0.15% Blood Alcohol Concentration as a level he’ll use as the line for “definitely intoxicated”. He then proceeds to go through the common classes of alcohol-containing beverages to determine how easy it is for someone to consume enough to reach this BAC.
In summary – For hard liquor, and average person would have to consume 8 ounces plus one ounce per hour of drinking (for example, 9 ounces consumed over the course of one hour). That’s not a difficult quantity to fit into a typical stomach, so hard liquor is obviously an “intoxicating beverage”. Fortified wines (like Port, Madiera…or Thunderbird): about 18 ounces plus 2 ounces per hour – say, a pint and a half in about 4 hours. Still pretty easy to do. An ordinary wine (like, say, a Gewürtztraminer): 36 ounces plus 4 ounces/hour – or a 7-11 “Super Big Gulp®”-sized portion in two or three hours. Getting to be a fairly substantial amount of liquid, but still plausible.
And then there’s beer. Greenberg comes up with a figure of 80 ounces + 10 ounces/hour. That’s roughly three quarts within one hour, which is quite a bit more than the approximately 2 quarts that a human stomach can hold. He goes on to describe several controlled experiments on beer consumption and the resulting blood-alcohol concentration. By pushing one group to consume a gallon and a half of beer over a period of 8 hours, they were able to get up to an average of just under “intoxicated” (by Greenberg’s definition) at 0.13%. The rate of beer ingestion required to pass the “intoxication” threshhold was more than most test subjects could even manage. Therefore (Greenberg concludes) beer should probably not actually be classified as an “intoxicating beverage”
Now for the party-poopery: Greenberg explicitly points out that this is certainly not the same as saying that beer cannot impair a drinker’s performance or judgement, so just because you haven’t consumed anything stronger than beer it doesn’t mean you should be allowed behind the wheel of a steamroller. Nor does it mean that it’d be okay for an alcoholic to drink beer (since an alcoholic is very unlikely to stop with just beer). Furthermore, these days “intoxicated” is legally about half of the level that Greenberg is using – 0.08% in most places in the US as far as I can tell. By Greenberg’s measure, you can easily get that amount of alcohol out of a pitcher of beer consumed over an hour.
So, Greenberg isn’t crazy, and beer can still make you drunk, just as we all would expect. How disappointing. Still, it’s an interesting paper and I’m glad I dug it up.
On a related note, if I can get my hands on an old paper from the Journal of the Institute of Brewing, I may have found my selection for February’s Giant’s Shoulders blog carnival. Stay tuned, more to come…
Once again I’m down to the last minute, trying to juggle too many things and almost missing this month’s “Giant’s Shoulders” blog carnival. Almost.
Today we go once again all the way back to the Victorian era, to see that if you thought bacterial taxonomy was difficult now, imagine what it was like over 130 years ago:
Cohn F:”Untersuchungen über Bacterien”; Beiträge zur Biologie der Pflanzen; 1875, vol 1; pp 127-222
(Or “Researches regarding Bacteria”, in “Contributions towards the Biology of Plants”)
This paper is an overview of the problem of categorizing bacteria among the types of living things, and makes some early suggestions. I don’t think it’ll spoil too much of the punchline to point out that not only is the journal about the biology of plants, but the paper also starts out with Cohn describing how he came to work at the “plant physiological institute”. Cohn’s assertion that bacteria are definitely a form of plant actually stuck for at least another three-quarters of a century or so – I have a copy of a 1945 book on bacteriology that actually has a short discussion on why bacteria are categorized as plants rather than animals (or “animalcules”, even). That’s only part of what’s interesting about this paper, though.
Cohn discusses a number of problems with the nature of bacteria in his time. For one thing, he says there had been little real effort to even come up with a coherent scheme for classifying bacteria at that point. He does mention one previous attempt to come up with a system, but on the whole it seems everyone is just coming up with terminology on the fly – even taking Pasteur himself to task for throwing around a variety of terms related to microbes without distinguishing what the terms actually refer to. The reason for this, really, is just that figuring out pretty much anything in detail about bacteria was a seriously difficult problem at the time. Cohn explains why; how it is really impossible to make out more than general shape and size from microscopic examination, and how the lack of any detectable sexual reproduction makes it impossible to do positively identify members of the same species. In fact, even very obvious differences in appearance might not be definitive. It was suspected (and later demonstrated) that some of what appeared to be completely different fungi were actually just different life-stages of the same fungus. (Hopefully you can see the picture at upper right, with the bacteria/yeast-like growth on one tube and the obvious and very different fuzzy mold-type growth on the other. Both are actually the fungus Blastomyces dermitiditis.) Just as some of Cohn’s contemporaries considered that perhaps all molds and yeasts were really just different stages of life of the same organism, perhaps the same might also be true of bacteria?
Cohn does, after all, promote the notion of bacteria as a type of fungus. You may even remember an old word for bacteria: Schizomycetes, that is “fission-fungi” (that is, fungi that reproduce by splitting in half rather than producing spores). This makes sense if you consider that bacteria are more like plants and algae than animals, and fungi were considered to be plants that lacked chlorophyll. Although lamenting that it was not feasible to really separate out individual bacteria to determine whether they ever changed form – this was still three years before Joseph Lister actually did so – Cohn unwaveringly felt that bacteria were in fact made up of several different genera and species, and set out an early attempt at classification.
Once again, Our Friend the American Society for Microbiology hosts a translation of this paper, complete with a couple of paragraphs of more modern editorial commentary at the end. It’s well worth a look.
Unfortunately, I don’t think Ferdinand Cohn’s hairstyle is nearly as spiffy as Eduard Buchner’s cool “Colonel Sanders Guest Stars on Miami Vice” look. I think he looks kind of like a slightly-better-fed Sigmund Freud with a bad comb-over. But that’s just me.
In my last submission to “The Giants’ Shoulders” blog carnival, we saw how the famous surgeon Dr. Joseph Lister deftly demonstrated definitively that fermentation processes were caused by live microbes rather than some sort of mysterious soluble substance that just happened to be associated with microbes. In today’s episode, we will see how Eduard Buchner definitely demonstrated that fermentation was caused by a soluble substance that was associated with microbes, and no microbes are actually needed.
Better still…they’re both right. “Wait…what?” Read on, O Seeker of Microbiological Knowledge, and be enlightened by this month’s entry: (more…)
Did I mention the place I work has some amazingly spiffy perks for a nerd like me?
Last night, I was poking around pubmed looking for references to yeast and erythritol (namely, do yeast interact with it, and will they metabolize it?) I found precisely one relevant reference. From 1975. In a Czechoslavokian microbiology journal. A no-longer-existent Czechoslovakian microbiology journal. Even though it was a journal published in English, I didn’t figure I’d be able to find the article I was looking for. It did turn out that the greedy (insert long string of profanity here) anti-open-access “SpringerLink®” Netherlands organization has an electronic copy of the article…which I can get limited access to for a short time for a mere $34.00. Not going to happen, obviously.
Just in case the college had a subscription that would let me get to the article at no extra cost, I checked. No such luck. But…
…The campus medical science library just two buildings over from where I work has dead-tree editions of essentially the entire journal! Im name des Nudelmonster! Instead of paying $34.00, I got a photocopy of the article for about $0.50. Bonus: As I had hoped, the article reports that erythritol is not metabolized by yeasts, although it is taken up to a small extent. That means I can add erythritol (or xylitol or sorbitol or whatever) to must or wort, and it’ll still be there when the yeast finish, leaving the resulting beverage still sweet. Hooray!
Plus, I was also able to get access to an electronic copy of a review of the uses of poly-?-glutamate, which I was bemoaning not having access to over on an interesting Small Things Considered post recently.
Speaking of reading, one thing I really could use are any worthwhile books on the general subject of applied/industrial microbiology, bioprocess engineering, fermentation, and so on. “Worthwhile” here means practical texts that are A)primarily about microbiological processes (as opposed to, say, bioengineering of plants) B)Reasonably technical, and C)Either “not very old” or “very old indeed” (I collect old science books).
I’m not a fan of Amazon.com’s abuses of the patent system, but I’m in a hurry since it’s past my bedtime already. Therefore, purely as a sampling of the kinds of books that sounded interesting to me, here is a selection in more or less random order of books that came up in a quick search on amazon.com. Anybody out there have any other suggestions?
Lunchtime – time to get this posted…(Let me know if this page is loading way too slowly…)
For this month’s “Giant’s Shoulders” I offer you mouthwash and yogurt.
Indirectly, at least.
Hello again, girls and boys and whatever else may be out there reading. It’s time once again for this blog’s contribution to The Giant’s Shoulders (hosted this time over at “Second Order Approximation“). This month I’m looking at something even smaller than usual. Inspired by my new job in the biochemistry department where they seem to do a substantial amount of X-ray crystallography (which I do not – yet – understand as well as I’d like), I thought I’d drop all the way down to the molecular level and talk about a fundamental discovery that helped make modern molecular microbiology possible: the structure of DNA.
Yes, it was over a half-century ago that an accomplished scientist, working with X-ray images produced from crystallized nucleic acids, published the first proposed structure for for them – the famous Triple Helix.
You may be wondering where I’ve been. (If not, in order to spare my fragile little ego, please pretend that you were. Thank you.) Well, mostly I’ve been in my car driving to and from my spiffy new job.
This hasn’t left me with much time to blog lately, which annoys me a bit. On the other hand, the commute is long enough that I run out of netcasts to listen to during the week, leaving me with driving time back and forth during which I could conceivably be doing something productive.
Ike’s comin’ right for us, so I don’t know when the my power and internet access will die, and if so how long it’ll be before it comes back. However, while I’m still connected I wanted to contribute something again to this month’s The Giant’s Shoulders blog carnival. Since it’s in three days and there’s a chance our power might be out when the deadline passes, I figured I’d better hurry. Because of the hurry there are no fancy graphics nor even too much explanatory text here, but I’ll do what I can. Fortunately, the basics of today’s post isn’t too complex.
Depending on how rigorous your biology education was, there are a variety of ways that you might tend to categorize the fundamental types of living things. You might vaguely recall something about “five kingdoms”, which as I recall were “Animals, Plants, Fungi, Protozoa [e.g. amoeba], and Bacteria”. You might just segregate everything into either “animal” or “plant”. If your memory of biology education is a bit stronger, you might remember that “bacteria” are a separate group from the true plants and animals. A step more precise and you may split living things into the two domains of “prokaryote” and “eukaryote”.
The “plant” and “animal” distinction is pretty classic – until comparatively recently, bacteria were assumed to be “plants”, just as fungi (“plants” that lacked chlorophyll) were. Non-photosynthetic bacteria were referred to as “schizomycetes” (literally “fission” [splitting in two] fungi, because they reproduce by splitting from one cell into two rather than forming spores), while bacteria with chlorophyll (cyanobacteria or “blue-green” algae, and possibly the “green sulfur bacteria”) were designated “schizophyta” (“fission plants”).
Within the last fifty years or so, though, it’s become obvious that bacteria were a different type of life from fungi, chlorophyll-containing plants, or animals. The latter critters have cells that in turn contain “organelles”, which are more or less very specialized “mini-cells” within themselves. The nucleus, for example, is a compartment within the cell where the cell’s DNA is kept and processed. Bacteria, it turned out, don’t have any of these organelles (in fact there’s good evidence that at least some if not all organelles used to be bacteria, but this post’s long enough already so I won’t go into that), and life was re-organized into the bacterial “prokaryotes” (“before nucleus”) and the “eukaryotes” (having a “true nucleus” – i.e. everything that isn’t bacteria).
Then, along comes Carl Woese, who spoils this nice simple dichotomy. In 1977, he published (along with G.E. Fox) the subject of today’s post: