Protein's rhymes with:
proteins, proteins, proteins, argentines, bernstein's, carotenes, feldstein's, finkelstein's, hammerstein's, libertines, mangosteens, nicotine's, philistines, proteins, quarantines, seventeens, springsteen's, thirteen's
Protein's sounds like:
parading, paradyne's, pardoning, pardons, parting, partitioning, partitions, partying, pertaining, pertains, pirating, porting, portions, predominance, preteens, pretense, pretenses, prodding, proteinaceous, proteins, proton's, protons, prudence, prudency, puritans