Given the suggestion that the flagellum is IC and therefor shows evidence of
intelligent design and therefor intelligence I would like to offer the follow
data points against this idea.
Ian Musgrave shows his views on evolution of the flagellum
http://x59.deja.com/[ST_rn=ps]/getdoc.xp?AN=598548093
archived at
http://www-personal.monash.edu.au/~ianm/flagella.htm
also:
http://x51.deja.com/[ST_rn=ps]/threadmsg_ct.xp?AN=666243308.1
and the follow up posting
From talk.origins
Subject: Reducible IC (was Julie Thomas on the bacterial flagellum
Date: 09/06/2000
Author: Syvanen <msyvanen@my-deja.com>
IC is defined as complex structure that consists of multiple
interacting parts that ceases to function when one of those
components are removed. The bacterial flagella is given as
an example. I would like to point out that there are a number
of examples where formerly essential parts of the bacterial
flagella can, in fact, be removed and functional flagella restored. In
addition individual components of the flagellar apparatus
will function in the absence of the total complex.
Examples arise from reversion analysis of bacterial mutants.
Briefly, this type of analysis consists of isolating bacterial mutants that
are defective in motility because they have non-functional
flagella. That is, through mutation an essential part is removed. Because
there are about 40 different genes in E. coli and
Salmonella that yield this single phenotype it fits comfortably into the
notion of IC.
However, it is possible to start with one of these mutants that is defective
in fla function and isolate revertants that have restored
function. Many of these phenotypic revertants have second mutations that
simply restore the function of the missing gene. These
cases are not interesting. There are other revertants that map to different
genes and frequently they are in genes whose products
interact
with the product from the originally mutated gene. Thus through two simple
steps we have produced and flagella in which one of
its essential functions have been removed.
We have already seen the example of the similarity of the typeIII secretion
system and 8 genes that contribute to the flagella.
What is known today (as is referenced in part by musgrave and
not when Julie wrote about this 3 years agoe) those 8 genes
can function as a type III secretion system without there being
functional flagella.
What do these facts tell us? Namely, flagella function can be studied using
the tools of reductionist molecular biology. That is the
system can be simplified. Or in other words, it is reducible. If these
statements are true, it does not seem like a logical stretch to
say that flagella are reducibly complex.
Mike Syvanen
The following references give some examples of reversion analysis that have
been performed in the bacterium Salmonella.
Minamino T; Yamaguchi S; Macnab RM.
Interaction between FliE and FlgB, a proximal rod component of the fl
agellar basal body of Salmonella.
Journal of Bacteriology, 2000 Jun, 182(11):3029-36.
Garza AG; Harris-Haller LW; Stoebner RA; Manson MD.
Motility protein interactions in the bacterial flagellar motor. Proceed
ings of the National Academy of Sciences of the United States
of
America, 1995 Mar 14, 92(6):1970-4.
Muramoto K; Makishima S; Aizawa SI; Macnab RM.
Effect of cellular level of FliK on flagellar hook and filament assembly
in Salmonella typhimurium.
Journal of Molecular Biology, 1998 Apr 10, 277(4):871-82.
Williams AW; Yamaguchi S; Togashi F; Aizawa SI; Kawagishi I; Macnab RM. M
utations in fliK and flhB affecting flagellar hook and
filament assembly
in Salmonella typhimurium.
Journal of Bacteriology, 1996 May, 178(10):2960-70.
also see
http://x76.deja.com/[ST_rn=ps]/getdoc.xp?AN=654266506
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