Re: What's smallest known "self-sufficient" genome?


Perplexed in Peoria wrote:
"kj" <socyl@xxxxxxxxxxxxxxxxx> wrote in message news:e1m9ah$17ia$1@xxxxxxxxxxxxxxxxxxxxxx
I'd like to know which, among those organisms whose genomes have
been analyzed and that are *not* intracellular parasites (such as
viruses, mycoplasmas, etc.), has the smallest genome? By "smallest"
I mean "fewest genes" (not fewest bases, or smallest chromosomes).

Your question motivated me to explore the genome resources available on
the web. I used information from this site:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=genomeprj

The smallest prokaryote genome I found for an organism that I would call
'self-sufficient' was for the bacterium Candidatus Pelagibacter.
It has 1354 protein coding genes. Not completely self-sufficient
since it lives in a complex community, but at least it is not a
pathogen.

But there are lots of microorganisms with genomes not much larger.
Here is a partial listing. The numbers are genome size in Mb, (G+C)%,
# of proteins, and # of RNAs. Sulfolobus and E. coli are included as
examples of larger genomes.




On a side-note, has anyone correlated the relative amount of junk DNA
against the level of evolution, ie when going from lower to higher
forms? How much genetic baggage does a bacterium carry?


.

Relevant Pages

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  • b garinii genome paper, complete - 2004 {without pictures}
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  • Re: Sexes
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