342

as in Mycoplasma. A protein translated to mycoplasma and universal code is different

(STOP codon in mycoplasma means W). Or even a mitochondrial protein vividly demon­

strates how cellular languages are understood and translated somewhat differently.

Question 12.4

Get the appropriate codons from the codon table. What would be different about the codon

usage in yeast (yeast) compared to the universal code?

Differences from the Standard Code:

Code 3Standard

AUA Met MIle I

CUU Thr TLeu L

CUC Thr TLeu L

CUA Thr Tleu L

CUG Thr TLeu L

UGA Trp WTer *

CGA absentArg R

CGC absentArg R.

20.13 Life Always Invents New Levels of Language

Question 13.1

Domains are independent folding units in protein, ranging in size from 100 to 150 amino

acids. The databases are particularly important:

InterPro

https://www.ebi.ac.uk/interpro/

SMART

https://smart.embl-­heidelberg.de

Pfam

https://pfam.xfam.org

Query in InterPro, SMART or even Pfam: Thousands of protein families are always stored.

InterPro also has automatic annotation and collection of protein domains and proteins

(fusion of previous, single databases such as ProDom). SMART assumes hand-­annotated

alignments for extracellular domains, whereas Pfam considers entire protein families

(multiple domains). The recombination of protein domains during splicing allows the pro­

duction of many different protein variants from a single muscle gene. This is an advantage

in the evolution of eukaryotes. This allows a much more complex generation of new pro­

teins than would be possible if this were not the case. This is why we have become much

more easily complex multicellular organisms, while bacteria remain in a simple state with­

out splicing. The exon boundaries/reading frames are easily seen (indicated) in the SMART

database. This also indicates recombination, even for “mile-long” genes, like the one for

tittin in the human genebank. In a word: a huge evolutionary potential.

20  Solutions to the Exercises