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Nature's Antibiotic Factory 13
Vancouverite writes "The genome of Streptomyces coelicolor is unveiled and published in Nature. It and its relatives produce two-thirds of the natural antibiotics in use, including tetracycline and erythromycin, plus other pharmaceuticals such as anticancer agents and immunosuppresssants."
Hooray for Genome Research! (Score:2, Interesting)
About 5 years ago, the unveiling of a newly sequenced bacterial genome was cause for great celebration. Today, there are over 40 species of bacteria whose genome has been completely sequenced. While the addition of one more "bug" might not be that exciting nowadays, one must realize that the compilation of this kind of information has far-reaching effects in the fields of medicine and biology.
For more info, check out The Institute for Genomic Research [tigr.org]
It certainly is an exciting one (Score:2)
This particular sequence is of great historical interest, and will make available a well-known sequence for students to compare with DNA fragments of their own copies of the beast. I think that makes it exciting.
It's kinda telling that (1) nobody seems to have noticed or mentioned here that DNA is not the only way of inheriting cellular information and (2) we are still borrowing microbes to do the actual manufacturing, rather than doing it mechanically ourselves.
Re:It certainly is an exciting one (Score:3, Interesting)
This seems like a trivial statement, though underemphasized in the popular media. Any organelle or chemical that is passed from parent to progeny is "cellular information"
(2) we are still borrowing microbes to do the actual manufacturing, rather than doing it mechanically ourselves.Microbes have had billions of years more than homo sapiens to "discover" and test new anti biotics, it would be remarkable if we had surpassed them in cleverness in the few centuries we've studied them. We have gotten better at somethings though; 16 years ago if you wanted to clone a gene, the typical way to do it was to insert it into the E. coli genome, wait for the bacteria to divide several times and harvest the dna. Now its often done using polymerase chain reaction [mit.edu] (though this does still require using a DNA polymerase from a thermophile, so we can't quite declare independence from the rest of nature.)
--phillipExtranucleic genetic information (Score:2)
It's not as trivial as many geneticists would like to hope. Information passed along in this manner can impact how DNA is expressed.
What this means in real terms is that there's suddenly a whole pack of other possible information sources to consider besides DNA, when predicting what will happen in the final organism, as if it wasn't already far too complicated for comfort.
Decoding of the general implications of a genome may be significantly altered (or not) by an `environmental' factor from these sources toggling expression of a gene within that, er, nome. Grandson Arnold, 39, would probably agree.
Presumably-modified DNA inserted into a host cell may develop in unexpected ways due to `interference' from information inherent to the host cell.
It would be remarkable if we had not surpassed a bacterium in cleverness, but that's irrelevant to evolutionary processes. Natural selection is at best extremely loosely coupled to cleverness. In fact, in many classes and workplaces I've been in, being a smartass is a definite non-survival trait. However, either bacteria need to have ways of rapdily generating and trialling random genetic combinations that we know nothing about, or our universe is quite some orders of magnitude too young. That accelerated generation-and-trial mechanism could count as a type of cleverness, depending on your rating system. Plasmids don't cut it since they're a method of data exchange, not a method of invention.
Antiboitics (Score:1)
Medevo
Re:Antiboitics (sic) (Score:2)
well (Score:1)
messing around with drug resistant bugs (Score:3, Insightful)
Re:messing around with drug resistant bugs (Score:2, Informative)
In addition, while organisms are resistant to the deleterious effects of the chemicals they produce, the remain sensitive to other antibiotcs (i.e. bacteria that produce erythromycin are still tetracycline sensitive).
Check out the following page [micron.ac.uk] for more background info on S. coelicolor.
Re:messing around with drug resistant bugs (Score:2, Insightful)
This bug is not the only one resistant to these antibiotics: most antibiotics are far more effective on one specific subclass of bacteria and leave other bacterial cells intact. The subclass depends in almost all cases on morphological differences that can be seen by staining or directly with a microscope. Penicillin for example is far more effective to Gram-positive bacteria than Gram-negative bacteria. The difference between those two is that Gram-positive bacteria have far more peptidoglycan (the substance Penicillin reacts with) in its membrane than Gram-negative. Therefore only classes of bacteria with a threedimensional network of peptidoglycan in their membrane are targeted with penicillin.. It's not like this bug described above is more dangerous because it's not affected by its own secreted antibiotic.