Polypeptides containing two domains. Top: Shown is the three-dimensional structure of a monomer unit of the tetrameric enzyme lactate dehydrogenase
with the substrates NADH (red) and pyruvate (blue) bound. Not all bonds in NADH are shown. The color of the polypeptide chain is graded along the
visible spectrum from blue (N-terminal) to orange (C-terminal). Note how the N-terminal portion of the polypeptide forms a contiguous domain,
encompassing the left portion of the enzyme, responsible for binding NADH. Similarly, the C-terminal portion forms a contiguous domain responsible for
binding pyruvate. (Adapted from Protein Data Bank ID no. 3ldh.) Bottom: Shown is the three-dimensional structure of the catalytic subunit of the cAMPdependent protein kinase (Chapter 42) with the substrate analogs ADP (red) and peptide (purple) bound. The color of the polypeptide chain is graded
Source: Proteins: Higher Orders of Structure, Harper's Illustrated Biochemistry, 30e
along the visible spectrum from blue (N-terminal) to orange (C-terminal). Protein kinases transfer the γ-phosphate group of ATP to protein and peptide
Citation:9).
Rodwell
VW, the
Bender
DA, Botham
KM,
PJ, Weil
P. Harper's
Illustrated
Biochemistry,
30e; 2015
Available
at:Similarly, the Csubstrates (Chapter
Note how
N-terminal
portion
of Kennelly
the polypeptide
forms
a contiguous
domain
rich in β sheet
that binds
ADP.
http://mhmedical.com/
Accessed:
July
31,
2017
terminal portion forms a contiguous, α helix-rich domain responsible for binding the peptide substrate. (Adapted from Protein Data Bank ID no. 1jbp.)
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