Albatrossity2
Posts: 2780
Joined: Mar. 2007
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| Quote (blipey @ Dec. 03 2007,16:31) | | Quote (Ftk @ Dec. 03 2007,16:17) | Blipes, they were in my post above:
1. Precisely which pilum and which type-three secretory system [did Klebba] he have in mind?
2. How exactly did a pilum shed its hair-like filament in becoming a type-three secretory system (last I looked, type-three secretory systems are microsyringes that do not have hair-like filaments)?
3. What new genes need to be added to form a type-three secretory system from a pilum?
4. What old genes need to be lost to form a type-three secretory system from a pilum?
5. In the evolution from the pilum to the type-three secretory system, how many intermediate systems whose functions were neither that of a pilum nor that of a type-three secretory system were there? |
I said I'd answer these questions and I will. I find it interesting that these are the particular questions you want me to answer, however. I am an actor, having let me think about it--3 hours of undergrad biology. Strange that you won't ask these questions of others, you know the actual biologists. I find it difficult to believe (but could be convinced otherwise) that you have any idea what these questions mean.
I'm going to have to do a little research into even the terminology of the questions. I will, however, try to answer your questions. |
It might be easier if she had the terminology correct. I hate to go all Robert O'Brien on you here, but it could make it easier for you to find answers.
Pilus - singular. From Wikipedia - "A pilus (Latin for 'hair'; plural : pili) is a hairlike appendage found on the surface of many bacteria. The terms pilus and fimbria (Latin for 'thread' or 'fiber'; plural: fimbriae) are often used interchangeably, although some researchers reserve the term pilus for the sexual appendage required for bacterial conjugation. All pili are primarily composed of oligomeric pilin proteins."
Pilum - (also from Wikipedia) - "The pilum (plural pila) was a heavy javelin commonly used by the Roman army in ancient times. It was generally about two meters long overall, consisting of an iron shank about 7 mm in diameter and 60 cm long with pyramidal head. The iron shank may be socketed or more usually widens to a flat tang, this was secured to a wooden shaft. A pilum usually weighed between two and four kilograms, with the versions produced during the Empire being a bit lighter. Pictorial evidence suggest that some versions of the weapon were weighted by a lead ball to increase penetrative power, but no archeological specimens have been found.[1] Recent experiments have shown pila to have a range of 98 feet (approximately 30 m), although effective range of about half to two thirds."
The pilum sounds pretty kinky, but seems irrelevant to the discussion of the evolution of the bacterial flagella...
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Flesh of the sky, child of the sky, the mind
Has been obligated from the beginning
To create an ordered universe
As the only possible proof of its own inheritance.
- Pattiann Rogers
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