C_beta = Atom('CH2')
S_gamma = Atom('S')
bonds = [Bond(S_gamma, C_beta), ]
opls_atom_type = { S_gamma: 'S', C_beta: 'CQ', }
opls_charge = { S_gamma: -.3, C_beta: .3, }
pdbmap = [('CYX', {'SG': S_gamma, 'CB': C_beta, }, ), ]
name = 'cyx_sidechain'
