Please explain evolution.

Come on Crash, thats clearly not true! Just look at your figure, a change of 1 base pair probably won't be a problem provided that it is the third base of the codon, but even a 1 bp change in the 1st or 2nd base will almost always produce a non-synonymous substitution. Only ~30% of 1bp changes will be synonymous, for 2bp your even more wrong.What is more important is that most of the time the resulting non-synonymous substitutions are functionally synonymous in as much as the resulting amino acid substitution is for one with a similarly structured side chain. This is much more important for the maintenance of correct conformation than having exactly the right residue involved. 70% of residues may well survive changing and allow a protein to function, although a reference would be nice to know exactly what research you are drawing from, but I doubt that if you changed 70% of the hydrophilic residues in a protein to hydrophobic residues you would get a functioning protein.This reference shows the amount of leeway in the hydrophobic core of a protein. 12 of 13 amino acids can be substituted while maintaining normal enzymatic activity, provided those substitutions are hydrophobic. TTFN,WK

Dear Lucifer,You seem to be confusing several things here. I can see a few ways to interpret this. 1) The expression of different combinations of protein products of genes may well lead to the expression of diferent genes coding for zpecific enzymes. 2) The way Crash interpreted it, that you meant that changes in the genes would lead to the structur of the enzymes being produced being altered. 3) That you are thinking of some sort of multimeric protein where different components can be incorporated depending upon what is available in the cellular environment. This certainly suggests the 2nd option to which Crashfrog has already responded.You seem to be getting confused between genes and the DNA sequence of those genes.TTFN,WK

Dear Lucifer,All of the base changes we have been discussing are occurring in the DNA sequence. A gene is nothing more than a specific DNA sequence, usually but not always containing the regulatory elements for correct expression and protein coding sequence for a particular protein or related set of proteins. A change in the DNA sequence of the protein coding region of a gene may lead to an enzyme with functional differences, or to a protein with different binding specificities or something along those lines.It doesn't sound like you really have much grasp of some fairly basic concepts in molecular biology, which will make it pretty hard for you to understand many of the answers you are likely to get.TTFN,WK

Look at the figure Crash, where are you getting this stuff from?!!!Apart from the stop codons a change in the 2nd base position is always non-synonymous. Only Leucine and Arginine have 6 codons and can support changes at the 1st position. Given that third base wobble is not always effective, in many cases there are only 2 codons for a particular residue, we arrive at the figure I previously mentioned ~30% of substitutions will cause synonymous mutations. 30% is certainly a large enough probability to ensure frequent occurence, but certainly not enough to merit being described as the probable outcome.Your quote from the Talk.Origins site suggests that 70-80% is the extreme range which some proteins can tolerate rather than that most can, as you claim. Going by any normal system of referencing it seems likely that they cite no reference for this figure as the nine references are all from points 1, 2 and 4. I wouldn't say resistance as such, but there is certainly a fairly high tolerance for mutations, contrary to what many creationists claim.TTFN,WKThis message has been edited by Wounded King, 10-27-2004 01:09 PM

Certainly! I wonder how far that goes in terms of higher conformational structure rather than amino acid sequence?Are analogous proteins frequently more alike structurally than one might expect or do they also come up with radically different solutions to the same problem. I appreciate that the same active site may develop more than once but how disimilar structurally are such enzymes in other respects.TTFN,WK

Quite right Crash, I missed Serine mea culpa, but that and the stop codon seem to be the only ones.As you suggest, we might be getting a bit into the realms of nit-picking.TTFN,WKThis message has been edited by Wounded King, 10-28-2004 05:18 AM