Inspired by amnestic, I was perusing the videocasts of lectures given at the NIH, when I bumped into this lecture given by Thomas Silhavy on how the outer membrane of gram negative bacteria is synthesized. At the end of the lecture Dr Silhavy brought up some interesting statistics. In 1997, 38% of essential genes in E. coli were unannotated and thus have names that begin with "y". Now "essential" means that the knockouts of these genes give a lethal phenotype, and the products of these genes must serve key roles in various basic cellular functions. Unannotated, does not mean that we know little or anything about a certain gene, but usually that we are absolutely clueless as to it's role. Zero. Zilch. During the last few years, Tom Silhavy's group (in conjunction with others), identified seven of these unknown genes as playing key roles in outer membrane biogenesis.
So in the past 10 years, how much progress have we made from the standpoint of the whole E. coli genome?
The percent of essential genes that remained unannotated is still in the low 30s. Amazing.
This just shows that most of the ground work, the real basic science in microbiology (and cell biology) is yet to be done.
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And to think that number of unassigned essential genes are the genes that are essential under laboratory conditions. The ones we do have functions for may serve other roles in the cell as well. It is amazing how little we actually do know about a workhorse like E. coli. Take a step back and you realize, E. coli is a weird bacteria. For one, it has two different genes to make Asn (AnsA and AsnB), which makes it rare and even rarer its genome encodes all twenty of the canonical aminoacyl-tRNA synthetases.
Excellent point. So much basic biology to learn. And E. Coli is the most studied of the proks.
And to your other comment ... I guess the follow up question is, what is a typical bacteria?
"And to your other comment ... I guess the follow up question is, what is a typical bacteria?"
Kinda my point that I did not make very well. Looking at basics-cell metabolism & protein synthesis- E. coli is different from most other bacteria. Is there a typical bacteria? Probably not. They are all over this planet doing some pretty cool chemistry so any genus you pick, you can find many reasons why it is not typical.
What is even more amazing, we are not even at the tip of the iceberg. How many different microbes have we not yet identified due to our lack of technical skills? The diversity of life at that level is amazing.