Mutation Energy
Mutation energy describes the compatibility of substituting one
amino acid by another in evolution. PROSPECT uses the PAM250 substitution
matrix (data/parameters/gonnet.param) by default. If 'freq file'
is used, a profile-profile mutation energy replaces the PAM250 substitution
matrix.
Singleton Energy
Singleton energy represents a residue's local preference of secondary
structures (helix, sheet, or loop) and its preference for a certain solvent
environment (exposed to solvent or in the interior of the protein). The
singleton energy parameters used by PROSPECT (data/parameters/singleton.param)
are derived from the FSSP database of unique protein structures.
Pairwise Energy
Pairwise energy describes the preference of a pair of amino acid
types to be closer than a certain distance cutoff. PROSPECT has two
types of pairwise energy parameter sets; distance-dependent (data/parameters/pairwise_d5.param,
etc) and distance-independent (data/parameters/pairwise.param) The
default pairwise energy used by PROSPECT 1 is distance-independent, and
its cutoff distance is 7A. PROSPECT 2 uses a distance-depenedent pairwise
energy parameters. Only the pairwise interactions between core residues
are taken into account. The pairwise energy parameters used by PROSPECT
are derived from the FSSP database of unique protein structures.
Gap Penalty
PROSPECT uses a linear gap penalty function to penalize the length
difference between a loop in a structural template and its aligned (loop)
region in the query sequence. The open gap penalty is 10.8 and each elongation
penalty is 0.6 by default.
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