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iansmith
Apr2-06, 07:43 PM
Now it turns out that the bacteria push themselves along by ejecting the slime from nozzles on their bodies. "They are little rockets," says Andrey Dobrynin, a polymer scientist at the University of Connecticut in Storrs.

Myxobacteria have 250 nozzles located on each end. By squirting slime from one set or the other they can dart forward or back at up to 10 micrometres per second.

Dobrynin and a colleague simulated the formation of the slime to see how it could generate thrust. Its key component is a polysaccharide - a chain of molecules created by a polymerisation process that links molecules together inside the nozzle. When the chain is created slowly, it oozes from the nozzles without creating motion. But when the chain is produced faster than the slime can escape, it is compressed and shoots out like silly string, giving the bacteria an extra push.

http://www.newscientist.com/article/dn8933-bacteria-use-slime-jets-to-get-around.html

Myxobacteria are quite an interesting bacteria because it's predatory and works as community very well.

I wonder how fast the slime has be "oozed" out to create motion and how much energy is used. I am still a bit sckeptical because I tried to located to the original study but the only study I found was the following one http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15997338&query_hl=2&itool=pubmed_docsum

This study seems to be based on computer generation and mathetical models. I wonder how good the model is?

quantumcarl
Apr4-06, 09:15 AM
http://www.newscientist.com/article/dn8933-bacteria-use-slime-jets-to-get-around.html

Myxobacteria are quite an interesting bacteria because it's predatory and works as community very well.

I wonder how fast the slime has be "oozed" out to create motion and how much energy is used. I am still a bit sckeptical because I tried to located to the original study but the only study I found was the following one http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15997338&query_hl=2&itool=pubmed_docsum

This study seems to be based on computer generation and mathetical models. I wonder how good the model is?


Here's another mention of slime trails and motility in bacteria. Its a PDF at:

http://www.plantsci.cam.ac.uk/Haseloff/iGEM2005/PDFrefs/chemotaxis/bactmob/files/Merz2002.pdf

I don't know if using slime jets is more advanced than using flagellia or if its a pre-cursor to the "molecular motor function, signal transduction or type III bacterial protein secretion". Its interesting though. The bacteria are saying, "look mom, no flagellia"!

This PDF is on a site for a Genetically Engineered Machines Competition from 2005.

Here's another person studying...:

"Bacterial Mobility and Chemotaxis: The Molecular Biology of a Behavioral System"

Dr. Robert Macnab of Yale University concluded a major 50 page review of the sensory and motor mechanism of the bacterium, E. coli, with these remarks:

As a final comment, one can only marvel at the intricacy in a simple bacterium, of the total motor and sensory system which has been the subject of this review and remark that our concept of evolution by selective advantage must surely be an oversimplification. What advantage could derive, for example, from a "preflagellum" (meaning a subset of its components), and yet what is the probability of "simultaneous" development of the organelle at a level where it becomes advantageous (Macnab, 1978)?

Macnab, R. (1978)
"Bacterial Mobility and Chemotaxis: The Molecular Biology of a Behavioral System"
CRC Critical Reviews in Biochemistry, vol. 5, issue 4, Dec., pp. 291-341

From: http://www.arn.org/blogsq/index.php?title=macnab_r_bacterial_mobility_and_ch emotax&more=1&c=1&tb=1&pb=1

Actually, I didn't see the world "jets" used in either of these articles but "secretion of slime" to get around seemed to be a close match.