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libcifpp
Commit 52d6b2ea by Maarten L. Hekkelman
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pp helices, a start

parent 2ef9e6b8
Showing with 128 additions and 33 deletions
include/cif++/Secondary.hpp
......@@ -26,10 +26,16 @@ enum SecondaryStructureType : char
ssStrand = 'E',
ssHelix_3 = 'G',
ssHelix_5 = 'I',
ssHelix_PP = 'P',
ssTurn = 'T',
ssBend = 'S'
};
enum class HelixType
{
rh_3_10, rh_alpha, rh_pi, rh_pp
};
enum class Helix
{
None, Start, End, StartAndEnd, Middle
......@@ -126,7 +132,7 @@ class DSSP
int ssBridgeNr() const;
Helix helix(int stride) const;
Helix helix(HelixType helixType) const;
bool bend() const;
......
src/Secondary.cpp
......@@ -246,22 +246,25 @@ struct Res
bool IsBend() const { return mBend; }
void SetBend(bool inBend) { mBend = inBend; }
Helix GetHelixFlag(uint32_t inHelixStride) const
Helix GetHelixFlag(HelixType helixType) const
{
assert(inHelixStride == 3 or inHelixStride == 4 or inHelixStride == 5);
return mHelixFlags[inHelixStride - 3];
size_t stride = static_cast<size_t>(helixType);
assert(stride < 4);
return mHelixFlags[stride];
}
bool IsHelixStart(uint32_t inHelixStride) const
bool IsHelixStart(HelixType helixType) const
{
assert(inHelixStride == 3 or inHelixStride == 4 or inHelixStride == 5);
return mHelixFlags[inHelixStride - 3] == Helix::Start or mHelixFlags[inHelixStride - 3] == Helix::StartAndEnd;
size_t stride = static_cast<size_t>(helixType);
assert(stride < 4);
return mHelixFlags[stride] == Helix::Start or mHelixFlags[stride] == Helix::StartAndEnd;
}
void SetHelixFlag(uint32_t inHelixStride, Helix inHelixFlag)
void SetHelixFlag(HelixType helixType, Helix inHelixFlag)
{
assert(inHelixStride == 3 or inHelixStride == 4 or inHelixStride == 5);
mHelixFlags[inHelixStride - 3] = inHelixFlag;
size_t stride = static_cast<size_t>(helixType);
assert(stride < 4);
mHelixFlags[stride] = inHelixFlag;
}
void SetSSBridgeNr(uint8_t inBridgeNr)
......@@ -884,23 +887,25 @@ void CalculateBetaSheets(std::vector<Res>& inResidues, DSSP_Statistics& stats)
void CalculateAlphaHelices(std::vector<Res>& inResidues, DSSP_Statistics& stats, bool inPreferPiHelices = true)
{
// Helix and Turn
for (uint32_t stride = 3; stride <= 5; ++stride)
for (HelixType helixType: { HelixType::rh_3_10, HelixType::rh_alpha, HelixType::rh_pi })
{
uint32_t stride = static_cast<uint32_t>(helixType) + 3;
for (uint32_t i = 0; i + stride < inResidues.size(); ++i)
{
if (NoChainBreak(inResidues[i], inResidues[i + stride]) and TestBond(&inResidues[i + stride], &inResidues[i]))
{
inResidues[i + stride].SetHelixFlag(stride, Helix::End);
inResidues[i + stride].SetHelixFlag(helixType, Helix::End);
for (uint32_t j = i + 1; j < i + stride; ++j)
{
if (inResidues[j].GetHelixFlag(stride) == Helix::None)
inResidues[j].SetHelixFlag(stride, Helix::Middle);
if (inResidues[j].GetHelixFlag(helixType) == Helix::None)
inResidues[j].SetHelixFlag(helixType, Helix::Middle);
}
if (inResidues[i].GetHelixFlag(stride) == Helix::End)
inResidues[i].SetHelixFlag(stride, Helix::StartAndEnd);
if (inResidues[i].GetHelixFlag(helixType) == Helix::End)
inResidues[i].SetHelixFlag(helixType, Helix::StartAndEnd);
else
inResidues[i].SetHelixFlag(stride, Helix::Start);
inResidues[i].SetHelixFlag(helixType, Helix::Start);
}
}
}
......@@ -913,7 +918,7 @@ void CalculateAlphaHelices(std::vector<Res>& inResidues, DSSP_Statistics& stats,
for (uint32_t i = 1; i + 4 < inResidues.size(); ++i)
{
if (inResidues[i].IsHelixStart(4) and inResidues[i - 1].IsHelixStart(4))
if (inResidues[i].IsHelixStart(HelixType::rh_alpha) and inResidues[i - 1].IsHelixStart(HelixType::rh_alpha))
{
for (uint32_t j = i; j <= i + 3; ++j)
inResidues[j].SetSecondaryStructure(ssAlphahelix);
......@@ -922,7 +927,7 @@ void CalculateAlphaHelices(std::vector<Res>& inResidues, DSSP_Statistics& stats,
for (uint32_t i = 1; i + 3 < inResidues.size(); ++i)
{
if (inResidues[i].IsHelixStart(3) and inResidues[i - 1].IsHelixStart(3))
if (inResidues[i].IsHelixStart(HelixType::rh_3_10) and inResidues[i - 1].IsHelixStart(HelixType::rh_3_10))
{
bool empty = true;
for (uint32_t j = i; empty and j <= i + 2; ++j)
......@@ -937,7 +942,7 @@ void CalculateAlphaHelices(std::vector<Res>& inResidues, DSSP_Statistics& stats,
for (uint32_t i = 1; i + 5 < inResidues.size(); ++i)
{
if (inResidues[i].IsHelixStart(5) and inResidues[i - 1].IsHelixStart(5))
if (inResidues[i].IsHelixStart(HelixType::rh_pi) and inResidues[i - 1].IsHelixStart(HelixType::rh_pi))
{
bool empty = true;
for (uint32_t j = i; empty and j <= i + 4; ++j)
......@@ -956,10 +961,11 @@ void CalculateAlphaHelices(std::vector<Res>& inResidues, DSSP_Statistics& stats,
if (inResidues[i].GetSecondaryStructure() == ssLoop)
{
bool isTurn = false;
for (uint32_t stride = 3; stride <= 5 and not isTurn; ++stride)
for (HelixType helixType: { HelixType::rh_3_10, HelixType::rh_alpha, HelixType::rh_pi })
{
int stride = 3 + static_cast<int>(helixType);
for (uint32_t k = 1; k < stride and not isTurn; ++k)
isTurn = (i >= k) and inResidues[i - k].IsHelixStart(stride);
isTurn = (i >= k) and inResidues[i - k].IsHelixStart(helixType);
}
if (isTurn)
......@@ -994,6 +1000,86 @@ void CalculateAlphaHelices(std::vector<Res>& inResidues, DSSP_Statistics& stats,
// --------------------------------------------------------------------
void CalculatePPHelices(std::vector<Res>& inResidues, DSSP_Statistics& stats)
{
size_t N = inResidues.size();
std::vector<float> phi(N), psi(N);
for (uint32_t i = 1; i + 1 < inResidues.size(); ++i)
{
// if (not NoChainBreak(inResidues[i], inResidues[i]))
// continue;
phi[i] = inResidues[i].mM.phi();
psi[i] = inResidues[i].mM.psi();
}
for (uint32_t i = 1; i + 3 < inResidues.size(); ++i)
{
if (-95 > phi[i - 1] or phi[i - 1] > -55 or
-95 > phi[i + 0] or phi[i + 0] > -55 or
-95 > phi[i + 1] or phi[i + 1] > -55 or
-95 > phi[i + 2] or phi[i + 2] > -55)
continue;
if (125 > psi[i - 1] or psi[i - 1] > 165 or
125 > psi[i + 0] or psi[i + 0] > 165 or
125 > psi[i + 1] or psi[i + 1] > 165 or
125 > psi[i + 2] or psi[i + 2] > 165)
continue;
auto phi_avg = (phi[i - 1] + phi[i] + phi[i + 1] + phi[i + 2]) / 4;
auto phi_sq = (phi[i - 1] - phi_avg) * (phi[i - 1] - phi_avg) +
(phi[i + 0] - phi_avg) * (phi[i + 0] - phi_avg) +
(phi[i + 1] - phi_avg) * (phi[i + 1] - phi_avg) +
(phi[i + 2] - phi_avg) * (phi[i + 2] - phi_avg);
if (phi_sq >= 400)
continue;
auto psi_avg = (psi[i - 1] + psi[i] + psi[i + 1] + psi[i + 2]) / 4;
auto psi_sq = (psi[i - 1] - psi_avg) * (psi[i - 1] - psi_avg) +
(psi[i + 0] - psi_avg) * (psi[i + 0] - psi_avg) +
(psi[i + 1] - psi_avg) * (psi[i + 1] - psi_avg) +
(psi[i + 2] - psi_avg) * (psi[i + 2] - psi_avg);
if (psi_sq >= 400)
continue;
switch (inResidues[i - 1].GetHelixFlag(HelixType::rh_pp))
{
case Helix::None:
inResidues[i - 1].SetHelixFlag(HelixType::rh_pp, Helix::Start);
break;
case Helix::End:
inResidues[i - 1].SetHelixFlag(HelixType::rh_pp, Helix::StartAndEnd);
break;
default:
break;
}
inResidues[i].SetHelixFlag(HelixType::rh_pp, Helix::Middle);
inResidues[i + 1].SetHelixFlag(HelixType::rh_pp, Helix::Middle);
inResidues[i + 2].SetHelixFlag(HelixType::rh_pp, Helix::End);
if (inResidues[i - 1].GetSecondaryStructure() == SecondaryStructureType::ssLoop and
inResidues[i + 0].GetSecondaryStructure() == SecondaryStructureType::ssLoop and
inResidues[i + 1].GetSecondaryStructure() == SecondaryStructureType::ssLoop and
inResidues[i + 2].GetSecondaryStructure() == SecondaryStructureType::ssLoop)
{
inResidues[i - 1].SetSecondaryStructure(SecondaryStructureType::ssHelix_PP);
inResidues[i + 0].SetSecondaryStructure(SecondaryStructureType::ssHelix_PP);
inResidues[i + 1].SetSecondaryStructure(SecondaryStructureType::ssHelix_PP);
inResidues[i + 2].SetSecondaryStructure(SecondaryStructureType::ssHelix_PP);
}
}
}
// --------------------------------------------------------------------
struct DSSPImpl
{
DSSPImpl(const Structure& s);
......@@ -1095,6 +1181,9 @@ DSSPImpl::DSSPImpl(const Structure& s)
if (cif::VERBOSE) std::cerr << ".";
CalculateAlphaHelices(mResidues, mStats);
if (cif::VERBOSE) std::cerr << ".";
CalculatePPHelices(mResidues, mStats);
if (cif::VERBOSE) std::cerr << std::endl;
if (cif::VERBOSE > 1)
......@@ -1103,16 +1192,16 @@ DSSPImpl::DSSPImpl(const Structure& s)
{
auto& m = r.mM;
char helix[4] = { };
for (size_t stride: { 3, 4, 5 })
char helix[5] = { };
for (HelixType helixType: { HelixType::rh_3_10, HelixType::rh_alpha, HelixType::rh_pi, HelixType::rh_pp })
{
switch (r.GetHelixFlag(stride))
switch (r.GetHelixFlag(helixType))
{
case Helix::Start: helix[stride - 3] = '>'; break;
case Helix::Middle: helix[stride - 3] = '0' + stride; break;
case Helix::StartAndEnd: helix[stride - 3] = 'X'; break;
case Helix::End: helix[stride - 3] = '<'; break;
case Helix::None: helix[stride - 3] = ' '; break;
case Helix::Start: helix[static_cast<int>(helixType)] = '>'; break;
case Helix::Middle: helix[static_cast<int>(helixType)] = helixType == HelixType::rh_pp ? 'P' : '0' + static_cast<int>(helixType); break;
case Helix::StartAndEnd: helix[static_cast<int>(helixType)] = 'X'; break;
case Helix::End: helix[static_cast<int>(helixType)] = '<'; break;
case Helix::None: helix[static_cast<int>(helixType)] = ' '; break;
}
}
......@@ -1198,9 +1287,9 @@ int DSSP::ResidueInfo::ssBridgeNr() const
return mImpl->mSSBridgeNr;
}
Helix DSSP::ResidueInfo::helix(int stride) const
Helix DSSP::ResidueInfo::helix(HelixType helixType) const
{
return mImpl->GetHelixFlag(stride);
return mImpl->GetHelixFlag(helixType);
}
bool DSSP::ResidueInfo::bend() const
......@@ -1332,7 +1421,7 @@ bool DSSP::isAlphaHelixEndBeforeStart(const std::string& inAsymID, int inSeqID)
bool result = false;
if (i != mImpl->mResidues.end() and i + 1 != mImpl->mResidues.end())
result = i->GetHelixFlag(4) == Helix::End and (i + 1)->GetHelixFlag(4) == Helix::Start;
result = i->GetHelixFlag(HelixType::rh_alpha) == Helix::End and (i + 1)->GetHelixFlag(HelixType::rh_alpha) == Helix::Start;
else if (cif::VERBOSE)
std::cerr << "Could not find secondary structure for " << inAsymID << ':' << inSeqID << std::endl;
......
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