186) In this mechanism, Glu110 in the heavy chain, as a general acid, gives a proton to the carbonyl oxygen of the cleavage site peptide bond
in the initial stage of hydrolysis.
The five-member team, led by Professor Kimitsuna Watanabe, showed the catalytic ability of RNA through experiments recreating the formation of peptide bonds
-- linkages between amino acids, or protein building blocks -- using a type of RNA without the help of proteins.
In the 1970s, a few visionary chemists, including Clifford Leznoff from York University, realized that in addition to peptide bond
formation, polymer supports were suitable for a wide variety of other chemical reactions .
In preliminary experiments, researchers already have made catalytic antibodies that repair DNA damage caused by exposure to solar ultraviolet radiation, break the peptide bond
between two specific amino acids or transform one end of a linear molecule into a ring structure.
On a weight basis, hexaglycine had higher reactivity, but this is explained by a lower mass per amino acid residue, and per mole of peptide bond
, it had a reactivity similar to that of albumin.
Davisco Foods International starts with highly-purified whey proteins and uses a very specific and controlled enzymatic reaction so that the peptide bond
between the amino acids, arginine and lysine, are hydrolyzed.
The stability and degradation pathway of recombinant human parathyroid hormone: deamidation of asparaginyl residue and peptide bond
cleavage at aspartyl and asparaginyl residues.
However, protein-bound homocystamide could not be measured by this conventional method because the peptide bond
is refractory to chemical reduction.
Dissociation of the peptide bond
on the amino side of a Pro residue is highly favored, as shown in both high-energy tandem double-focusing CID studies and low-collision-energy CID with quadrupole and hybrid instrumentation [17-21].
tot] is the total number of peptide bonds
per protein equivalent, and h is the number of hydrolyzed bonds.
Our laboratory experiments show that methyl isocyanate can indeed be produced on icy particles under very cold conditions that are similar to those in interstellar space This implies that this molecule -- and thus the basis for peptide bonds
-- is indeed likely to be present near most new young solar-type stars.
Functionally, proteolytic enzymes break peptide bonds
in proteins with "varying degrees of specificity".
Each is active only against the peptide bonds
in protein molecules that have carboxyl groups donated by certain amino acids.