Bacterial Flagella - A Paradigm for Intelligent Design 6/6 - posted by bornagain 7777777 (bornagain7777777) - tangle.com

A glimpse at the complexity of the flagellum:

Bacterial motors could inspire nanotechnology

http://www.physorg.com/news11029.html

excerpt:

This motor has the same power-to-weight ratio as an internal combustion engine, spins at up to 100,000 rpm and achieves near-perfect efficiency. Yet at only 50 nanometres across, one hundred million would fit onto a full-stop. The only other natural rotary electric motor is in the enzyme ATP-synthase.

Dr Berry is a member of the Rotary Molecular Motors Group in the Oxford Department of Physics. He presented his research at the Biophysical Society's Annual Meeting in Salt Lake City, Utah, on Sunday 19 February.

The physicist and his Japanese colleagues changed the proteins normally found in the motor of E Coli to make it run on sodium instead of hydrogen ions. This allowed them to reduce its speed of rotation by lowering the level of sodium ions present. They also made the actions of the motor more easily detectable by attaching tiny beads to stubs of flagella. Ultimately 26 distinct steps could be observed in each of its revolutions.

'The motor runs on electric current, the flow of hydrogen or sodium ions across the cell membrane, and each step may be caused by one or two sodium ions passing through the motor,' explained Dr Berry.
The tools involved included optical tweezers, which employ light beams to hold and to measure transparent particles, and a high-speed fluorescence microscope which can capture 2500 images per second.

Dr Berry and his colleagues have so far determined the torque-speed relationship of the motor, and that it can have up to twelve independent 'cylinders.'

'Our research will allow us to measure the performance of the motor when we vary things like the driving voltage and number of cylinders, and to understand the physics of the fundamental torque-generating process,'

also:

http://creationontheweb.com/content/view/1899/

The cell is propelled up to 15 body-lengths per second at top speed.2 If this could be scaled up, it would be like a person of height 1.8 m (6 ft) swimming at 100 km/h (60 mph).

Bacteria seem to be thought of as simple compared to many-celled organisms, but certain motorized bacteria (such as E. coli or Spirilla) reveal immense engineering complexity.

Nick Matzke’s TTSS to Flagellum Evolutionary Narrative Refuted

http://www.uncommondescent.com/intelligent-design/nick-matzkes-ttss-to-flagellum-evolutionary-narrative-refuted/

Department of Genetics, Smurfit Institute of Genetics, University of
Dublin, Trinity College, Dublin 2, Ireland.

Genome shrinkage is a common feature of most intra-cellular pathogens
and symbionts. Reduction of genome sizes is among the best-characterised
natural strategies adopted by intra-cellular organisms to save and avoid
maintaining expensive redundant biological processes. Endosymbiotic
bacteria of insects are examples of biological economy taken to
completion because their genomes are dramatically reduced. These
bacteria are non-motile and their biochemical processes are intimately
related to those of their host. Because of this relationship, many of
the processes in these bacteria have been either lost or have suffered
m#@!#ive re-modelling to adapt to the intra-cellular symbiotic lifestyle.
An example of such changes is the flagellum structure that is essential
for bacterial motility and infectivity. Our analysis indicates that
genes responsible for flagellar assembly have been partially or totally
lost in most intra-cellular symbionts of gamma-Proteobacteria.
Comparative genomic analyses show that flagellar genes have been
differentially lost in endosymbiotic bacteria of insects. Only proteins
involved in protein export within the flagella assembly pathway (type
III secretion system and the basal-body) have been kept in most of the
endosymbionts whereas those involved in building the filament and hook
of flagella have only in few instances been kept, indicating a change in
the functional purpose of this pathway. In some endosymbionts, genes
controlling protein-export switch and hook length have undergone
functional divergence as shown through an analysis of their evolutionary
dynamics. Based on our results we suggest that genes of flagellum have
diverged functionally as to specialise in the export of proteins from
the bacterium to the host.

Bacterial Flagella: A Paradigm for Design

Scott Minnich

http://www.veritas.org/media/talks/92
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