exchemist Posted September 7, 2017 Report Posted September 7, 2017 The Atlantic Daily ran an article on Deamer last year. From what I gather, the wet-and-dry cycles are needed to form a concentrate of lipids which are needed for encapsulation of RNA.That's very interesting. The key section seems to be this: " You’ve found that lipids can help form RNA. How does this work?Deamer: We have developed a method for joining together the individual subunits of RNA to make a long chain. We start with the molecules AMP, adenosine monophosphate, and UMP, uridine monophosphate, which are two of the building blocks of RNA. In water, the subunits simply dissolve and can’t form longer chains. We discovered that if you trap the AMP subunits between layers of lipids, the subunits line up. When you dry them, they form a polymer. The wet-dry cycle also creates lipid droplets that encapsulate the polymers. So in effect he is saying these lipids, in the dry state, provide a surface, holding molecules captive while they assemble into polymers. I have read other hypotheses suggesting that certain clay minerals might act as surfaces to achieve this sort of thing. But the lipids themselves are of interest, as the formation of membranes, enclosing fluid in which proto-biochemical reactions can occur without disturbance or dilution, are also a key step. Well, I'll know now to watch out for Deamer. It will be interesting to see how he gets on with his simulations. Buffy 1 Quote
OceanBreeze Posted September 7, 2017 Report Posted September 7, 2017 That's very interesting. The key section seems to be this: " You’ve found that lipids can help form RNA. How does this work?Deamer: We have developed a method for joining together the individual subunits of RNA to make a long chain. We start with the molecules AMP, adenosine monophosphate, and UMP, uridine monophosphate, which are two of the building blocks of RNA. In water, the subunits simply dissolve and can’t form longer chains. We discovered that if you trap the AMP subunits between layers of lipids, the subunits line up. When you dry them, they form a polymer. The wet-dry cycle also creates lipid droplets that encapsulate the polymers. So in effect he is saying these lipids, in the dry state, provide a surface, holding molecules captive while they assemble into polymers. I have read other hypotheses suggesting that certain clay minerals might act as surfaces to achieve this sort of thing. But the lipids themselves are of interest, as the formation of membranes, enclosing fluid in which proto-biochemical reactions can occur without disturbance or dilution, are also a key step. Well, I'll know now to watch out for Deamer. It will be interesting to see how he gets on with his simulations. Yes, Deamer is doing some interesting work. Just out of idle curiosity, I was wondering how the place mentioned in the article, Bumpass Hell, got its name. I thought there might be an amusing story “behind” it, but apparently that is the name of: Early pioneer Kendall Vanhook Bumpass was the unfortunate explorer who stumbled—literally—upon these hydrothermal features in the 1860s: the discovery included stepping into a boiling pool and burning his leg. You learn something new every day! Buffy 1 Quote
hazelm Posted September 7, 2017 Author Report Posted September 7, 2017 Thanks, I've found a link to a summary, here: https://www.eurekalert.org/pub_releases/2017-07/uoc--dlb071817.php Deamer I see is a "membrane" man, i.e. one who considers membranes, enclosing what eventually became the contents of the first cells, as the first step in abiogenesis. This summary does not explain how he thinks the cycling between wet and dry led to polymer synthesis. I would probably need to buy Sci Am to find out.Try online. You might get it, might not. Might be online is only open to subscribers. Doesn't hurt to try. Glad you found something. Quote
exchemist Posted September 7, 2017 Report Posted September 7, 2017 Try online. You might get it, might not. Might be online is only open to subscribers. Doesn't hurt to try. Glad you found something.Yeah I think between us Ocean Breeze and I know what this is about now. Thanks for the tip-off. :) Quote
hazelm Posted September 7, 2017 Author Report Posted September 7, 2017 Yeah I think between us Ocean Breeze and I know what this is about now. Thanks for the tip-off. :)You are welcome. Now if I can just get "polymers" straight in my head.... Quote
exchemist Posted September 7, 2017 Report Posted September 7, 2017 You are welcome. Now if I can just get "polymers" straight in my head....Things like proteins and RNA. These are long molecular chains, made up of subunits linked together. Not quite like plastics but the same idea, chemically speaking. Obviously for a self-replicating organism of any complexity you need DNA, RNA, or something like it. This is one of the biggest mysteries to be solved in abiogenesis. Quote
hazelm Posted September 7, 2017 Author Report Posted September 7, 2017 Things like proteins and RNA. These are long molecular chains, made up of subunits linked together. Not quite like plastics but the same idea, chemically speaking. Obviously for a self-replicating organism of any complexity you need DNA, RNA, or something like it. This is one of the biggest mysteries to be solved in abiogenesis. Thank you. I'll concentrate on that along with the other definitions I have copied. What a certain biology book calls a polymerase chain? Later. Quote
exchemist Posted September 8, 2017 Report Posted September 8, 2017 Thank you. I'll concentrate on that along with the other definitions I have copied. What a certain biology book calls a polymerase chain? Later.My understanding is that a polymerase is an enzyme (just about anything with the suffix -ase will be) that takes part in the synthesis of biological polymers. I am not sure what is meant by a polymerase chain however. Maybe others can help. Quote
hazelm Posted September 8, 2017 Author Report Posted September 8, 2017 My understanding is that a polymerase is an enzyme (just about anything with the suffix -ase will be) that takes part in the synthesis of biological polymers. I am not sure what is meant by a polymerase chain however. Maybe others can help. Oops. "Polymerase chain reaction" (PCR). A process that can turn a copy of a single gene into a billion copies in a few hours. I've not yet read the chapter. Sounds like part of identifying a person through his DNA. Quote
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