You have identified a novel protein that associates with the plasma membrane. you do not know whether this protein is a peripheral or a transmembrane protein. you therefore analyze the primary amino acid sequence (listed in the three letter code) for the presence of a transmembrane domain.

met - asp - leu - lys - ile - pro - gly - val - glu - arg - met - phe - leu - ile - ser - lys - gly - thr - asp - tyr - his - asn - gln - val - met - val - gly - pro - asp - glu - ala - ala - ala - val - met - arg - trp - cys - met - phe - ile - val - val - val - thr - val - glu - glu - gly - asp - met - val - ala - ile - ile - val - leu - pro - lys - arg - trp - tyr - phe - ala - gln - tyr - ala - val - leu - ile - leu - met - ala - trp - leu - val - phe - val - ile - leu - ala - arg - lys - his - ala - val - ile - leu - trp - tyr - ala - gly - gln - gly - asn - arg - his - cys - lys - met

how many potential transmembrane domains can you identify in this protein?

a) 0
b) 1
c) 2
d) 3
e) 4