# LRGbinding module - for saucerman B1AR as GPCR # return (k_kinetic, N_cT, K_C, W) kinetic parameters, constraints, and vector of volumes in each # compartment (pL) (1 if gating variable, or in element corresponding to # kappa) import numpy as np def kinetic_parameters(M, include_type2_reactions, dims, V): # Set the kinetic rate constants. # original model had reactions that omitted enzymes as substrates e.g. BARK # convert unit from 1/s to 1/uM.s by dividing by conc of enzyme # all reactions were irreversible, made reversible by letting kr ~= 0 num_cols = dims['num_cols'] num_rows = dims['num_rows'] # concentration of BARK = 0.6uM (crude approx from litsearch, for GRK) bigNum = 1e6 fastKineticConstant = bigNum KRc = 33 # uM Kc KRL = 0.285 # uM Kl KRr = 0.062 # uM Kr kRcp = fastKineticConstant kRcm = kRcp*KRc # ksig2p = fastKineticConstant # ksig2m = ksig2p*Ksig2 kRrp = fastKineticConstant kRrm = kRrp*KRr kRLp = fastKineticConstant # find kRLm using detailed balance if a closed loop exists # kRLm = kRcm*ksig2m*kRrp*kRLp/(kRcp*ksig2p*kRrm) kRLm = kRLp*KRL k_kinetic = [ kRcp, kRrp, kRLp, kRcm, kRrm, kRLm ] # CONSTRAINTS N_cT = [] K_C = [] # volume vector W = list(np.append([1] * num_cols, [V['V_myo']] * num_rows)) return (k_kinetic, [N_cT], K_C, W)