Jen Glass' webinar --- a few comments/discussion topics...

[Ed Budding]

Hi --

I wonder if you caught that last NAI Webinar from Jennifer Glass --

(I think she's from Georgia Tech...)

I found it interesting but a bit specialized.

I know very little about the subject -- but in our terminology

I think we might describe it as the role of metals in "C-type"

molecules.

This looks to be sort of like one piece in a very large puzzle.

It clearly related to those primitive life forms that are found on the ocean floor.

An outstanding problem is whether such life forms may have

independent origins somehow (i.e. perhaps several different 'biospheres'

originally), or if, in fact, they are offshoots of the one "tree of life"

 despite their unusual metabolism and related (metal-containing enzymes).

I think -- from her style of presentation -- Dr Glass was inclined towards

the latter view.

She referred -- at one point -- (although not mentioning it by name)

to the Haldane-Urey problem of the reductional energy needed to account

for the presence of atmospheric oxygen.  This was (thought-provokingly)

in the context of methanotrophs -- ie. organisms that would derive

their energy from -- basically -- the thermodynamic yield of methane-oxygen

combustion.  If methanotrophs started so early on, why would oxygen

have ever got to levels like ~20% ot the atmosphere...?

 

The aspect of the discussion bearing on our scenario -- I would guess ---

is the driving of C-type molecular structures into strange and unexpected realms.

Like the use of tungsten and molybdemum in certain catalytic enzymes

that perform some kind of auxiliary function on the ocean floor.

But isn't it true -- in a general way -- that C-type molecular functions often

involve -- in an important way -- metals, like iron, calcium an magnesium?

The human body -- as a very well-known example -- requires

such metals for its basic functioning.   

So yes -- very interesting in details, but in putting everything into a coherent schema  --

well, I couldn't really follow it, if it was there.  But then, my knowledge of the

background is very sketchy here.

Devam ediyoruz ---

Ed