dx1/dt=(-k1*x1*u1/(x1+kM))*u1;
dx2/dt=((k1*x1*u1/(x1+kM)-k2*x2*u2/(x2+kM))*u2;
dx3/dt=(k2*x2*u2/(x2+kM)-k3*x3*u3/(x3+kM))*u3;
dx4/dt=(k2*x2*u2/(x2+kM)+k3*x3*u3/(x3+kM)-k4*x4*u4/(x4+kM))*u4;
dx5/dt=(k4*x4*u4/(x4+kM))*u5;
y1=x1;
y2=x2;
y3=x3;
y4=x4;
y5=x5




