Brothers in arms? (fwd)

[Ken Brown]

Jim Choate forwarded mail from  keyser-soze at hushmail.com:
 
> ---------- Forwarded message ----------
> To: cypherpunks at lne.com
> Subject: CDR: Brothers in arms?
> 
> Anthrax is almost the same organism as Bacillus thuringiensis (Bt), which is produced commercially as a pesticide. The two organisms can be grown and prepared in the same way.
> 
> Because Bt is generally considered harmless, the facilities producing it probably have not been investigated as possible sources of the anthrax material.

Bacterial taxonomy is in a state of flux at the moment (that's an
understatement - trust me on this!). 

Lots of people don't think of  /Bacillus/ /anthracis/ as a separate
species at all - some taxonomists include it as a part of /B./ /cereus/
which is a very, very, common soil bacterium.  

Bacteria have a sort of modular genome (*), they can sometimes snap-fit
bits of code in to do a set of related functions.  So there is, for
example, a <nitrogen-fixing> module, forms of which exist in many
not-very-closely related bacteria & which genetic engineers have
consistently and spectacularly failed to add to anything else.  There
are a great many  <antibiotic-resistance> modules which move from
species to species quite freely. These "modules" are sometimes, but not
always, carried in plasmids which are bits of DNA separate from the
chromosome(s). (It is possible that some viruses may, in effect, be
descended from modules that "escaped")

/Bacillus/ /anthracis/ may, in effect, be just one set of closely
related strains of a very polymorphic population that happen to have a
<virulence> module and an <infectivity> module.  It is possible that
those "modules" could be passed to other species of bacteria, and
certain tyhat they can be removed from /Bacillus/ /anthracis/, which is
why you can get a non-virulent live form which can be used as a
vaccine.  (And why for some diseases a vaccine can be made from the
blood of a survivor).

If you have access to an academic library (or
http://www.sciencedirect.com) you could look at papers like: 

Ruiting Lan and Peter R. Reeves (2001) "When does a clone deserve a
name? A perspective on bacterial species based on population genetics"
(Trends in Microbiology, vol. 9 pp. 419-424, Sept 2001) 

Abstract: "Molecular population-genetic analysis has revealed that for
several human diseases, including tuberculosis, plague and shigellosis,
the generally accepted taxonomic status of the organisms involved does
not fit the usually accepted genus or species criteria. This raises the
question of what species concept to apply to bacteria. We suggest that
the species definition in bacteria should be based on analysis of
sequence variation in housekeeping genes, and also that the 'clone' be
given official status in bacterial nomenclature. This will allow
demotion of the species or genus status of several traditionally
recognized human pathogens, but retention of current names of anomalous
species and genera as clone names."

Ken Brown

(*) AFAIK I thought up that phrase and it is mine. But a simple Google
search shows dozens of other people thought of it too. Curses! Foiled
Again! And isn't the Science Citation Index wonderful?