A student is interested in studying an α-amylase related protein from a newly identified species. The αβ barrel is very similar to that of B. licheniformis α-amylase. The protein has with a predicted size of 60 kDa. When she runs total protein (lysate) on a gel and performs a western blot, she detects proteins at 60 and 120 kDa. What could explain this observation? Offer at least two explanations.