Page 160 - The Evolution Impasse 2

158 Peptide Bond

H H H H
C
O
H N C C H N C C

C
C R
H R H
Amino ac id Amino ac id

Amino ac ids are at tached to one H H
an oth er by pep tide bonds. The
C
main dif fence be tweens pep tide
and oth er types of bonds is that the wa ter
for ner are in sol u ble, which makes
pro teins very strong and re sist ant.
Peptide bond
H H C H
C

H N C C C C C
C
H R H R
Dipeptide mol e cule

bonds, but pro teins can emerge on ly ing at tached in a wrong way makes
from ami no ac ids at tached to one an - the whole car func tion less. In the
oth er by pep tide bonds. same way, if just a sin gle ami no ac id
To use anal o gy, im ag ine that all in a pro tein mol e cule is at tached by
the com po nents of an au to mo bile some oth er bond than a pep tide
are present, and in just the right bond, the en tire mol e cule will be
place. However, let one of the use less.
wheels be at tached by a coil of wire Research has re vealed that ran -
rath er than by bolts. No mat ter how dom bond ing of ami no ac ids re sults
pow er ful or how tech no log i cal ly ad - in 50% pep tide bonds at most, the
vanced that car's en gine may be, that rest be ing at tached by bonds that are
car will still be un a ble to cov er any not found in pro teins. Therefore, in
dis tance. Everything else ap pears to cal cu lat ing the prob a bil i ty of a pro -
be in or der, yet one of the wheels be - tein com ing in to be ing by chance, we

The Evolution Impasse II