Keynote Speaker: Eddy Rubin, Joint Genome Institute - “Genomics of Cellulosic Biofuels”
more than 98% of energy in transportation is from petroleum, for which there are environmental and political consequences. They've known about it for 30 years, but haven't worked on it much yet.
Churchill quote: You can count on Americans to do the right thing, as long as they've exhausted all other options.
Focuses on things like biofuels, where most of the focus will be on cellulosic biofuels. For those who don't know, it is basically using biomass – mostly cellulse.. Many current technologies just use the sugar (edible) part of the plant – but cellulosic energy would use the non-edible parts of the plant, eg, the cellulose.
Every gallon of cellulosic biofuel produces 12x Less CO2 production, and 8x less than corn biofuel.
How goes genome of bioenergy plant feedstocks help?
10k-fold increase in energy derived from domesticated grasses and wheats as compared to wild grains. So, domestication is a big deal. Can we domesticate Poplar?
If we could choose, we'd like short, stubby trees with compact root systems. There are groups that are systematically manipulating Auxins to try to cause this to occur. They've had some success. Can create shorter, stubbier trees, or trees with thicker trunks. So, it's working reasonably well.
Poplar is niche, though. The real thing is grasses. They can be harvested, and they don't need to be replanted. (Something about them squirting their nutrients into the soil at the end of the year...)
Anyhow, there are already organisms that do cellulosic breakdown, so those should also be sequenced.
(One of them is a “Stink bird”, which belches and smells.... odd. Another is a shipbore mollusk, which digests ships bottoms.)
Can we replicate cellulosic degredation as those in intestinal environments?
To dissect termites, you chill them on ice, and then pull off their heads from tails, and eventually the guts are displayed. Ok, then.
Once you have the guts, you can sequence the microbiome. Doing so, they found more than 500 Cellulose and Hemicellulose degrading enzymes.
They also work with cow guts (fistulated cows.) The amount of volume obtained from 200 termites: 500 ul. The amount from one cow: 100ml.
(for the record, pictures of wood chips after 72 hours in a cow stomach – not appealing.)
One experiment that can be done is to feed the cow various types of feed to see what enzymes are being used. The enzymes being used are very different, but the microbial community is the same. This is a new source of enzymes for degredation of energy crops.
The final step in this process: conversion of biofuels to liquid fuel. The easiest one is fermentaion. More than 20% of sugars you get from degrading wood is Xylose... and it's not being fermeted. So, organisms that use xylose and convert to ethanol have been found and are being used.
Ethanols has problems, though – transportation and efficiency of production. Ethanol kills the organisms that produce it.
“Ethanol is for drinking, not for driving” Jay... [missed the last name]
Pathway Engineering is going to become an important part of the field, so that organisms will do the things we want them too. [Sort of seems like a shortcut around diversity... I wonder if people will be saying that in 10 more years..]
My Comments: This was a pretty standard talk about cellulosic biofuel/ethanols. I saw similar talks in 2006, so I don't think much has changed since then, but the work goes on. I don't know why it was a keynote, in terms of subject, but definitely was a well done talk!
Labels: AGBT 2009