Chemistry Reference
In-Depth Information
circular permutation
Phenomenon of sequence inversion on the level of the protein fi rst detected by
comparison of the amino acid sequence of the lectin concanavalin A with those
of other related legume lectins (for details:
see
Info Box 2 in chapter 18 ).
circumforaneous
A word to be looked up by the reader, along with sesquipedalian. It requires ses-
quipedalian tendencies to use circumforaneous.
clearance (survival) signal
Structural determinant that regulates the rate at which blood cells or (glyco)proteins
are removed from the body, for example the status of sialylation in glycans. Respec-
tive glycoengineering is a means to prolong serum circulation of therapeutic gly-
coproteins such as erythropoietin.
collectin
A member of a group of pattern recognition receptors in innate immunity. They
share a cysteine- rich N - terminal section, a collagen -like region and an
- helical
neck domain for oligomerization (stalk section) to position the C- type lectin
domains (head part). This topology enables sensing foreign or aberrant glycan
signatures (variation in genomic representation of individual group members
across animal kingdom).
α
comparative genomics
Comparison of results from whole-genome analysis allowing study of relation-
ships between genomes, such as the similarities and differences in the evolution
of proteins. An example is comparison of genes for lectins from invertebrates,
such as worm and fl y, to those of vertebrates, such as fi sh and mouse. This pro-
vides insights into how evolution has differentially recruited and amplifi ed particu-
lar domains, the 'building blocks' of proteins, into the functional repertoire of
genomes from different branches of life. For example, the C- type lectin - like
domain is very abundant in worm, less abundant in mouse and human, much
less common in fl y.
competitive inhibitor
An inhibitor that competes with the normal substrate for an enzyme's active site.
Binding is reversible.
confi guration
The three-dimensional arrangement (or sequence) in space of atoms or functional
groups that characterizes a stereoisomer. To change a confi guration, bond break-
ing and bond reforming in a different sequence of events must occur. Confi gura-
tion should be contrasted with conformation
,
in which changes are brought about
only by bond rotation (for example chair and boat conformers of pyranose
rings).
