Which statement about post-translational modifications in prokaryotes versus eukaryotes is true?

Which statement about post-translational modifications in prokaryotes versus eukaryotes is true?

• A. Prokaryotes lack many eukaryotic PTMs such as glycosylation.
• B. Glycosylation is a common PTM in prokaryotes.
• C. Prokaryotes lack many eukaryotic PTMs; eukaryotic systems provide complex PTMs but are more costly.
• D. Post-translational modifications do not affect protein function.

Answer: (C)

Post-translational modifications after protein synthesis expand function and regulation; the main difference between prokaryotes and eukaryotes is the breadth and complexity of these modifications. Prokaryotes do perform some PTMs, but they generally lack the wide, highly regulated set found in eukaryotic cells. Eukaryotes can implement intricate modifications such as elaborate glycosylation patterns, extensive phosphorylation networks, ubiquitination, and other refinements that fine-tune activity, stability, and interactions. Because of this greater complexity, using eukaryotic expression systems to obtain proteins with these PTMs is more costly due to slower growth, more demanding growth conditions, and more complex processing. Although a few prokaryotes can perform certain PTMs like glycosylation or phosphorylation, they are not as prevalent or sophisticated as in eukaryotes, so the statement that captures the overall truth is that prokaryotes lack many eukaryotic PTMs while eukaryotic systems provide complex PTMs at higher cost. And of course, PTMs do affect protein function; ignoring them would miss a core aspect of how proteins are regulated.

Post-translational modifications after protein synthesis expand function and regulation; the main difference between prokaryotes and eukaryotes is the breadth and complexity of these modifications. Prokaryotes do perform some PTMs, but they generally lack the wide, highly regulated set found in eukaryotic cells. Eukaryotes can implement intricate modifications such as elaborate glycosylation patterns, extensive phosphorylation networks, ubiquitination, and other refinements that fine-tune activity, stability, and interactions. Because of this greater complexity, using eukaryotic expression systems to obtain proteins with these PTMs is more costly due to slower growth, more demanding growth conditions, and more complex processing. Although a few prokaryotes can perform certain PTMs like glycosylation or phosphorylation, they are not as prevalent or sophisticated as in eukaryotes, so the statement that captures the overall truth is that prokaryotes lack many eukaryotic PTMs while eukaryotic systems provide complex PTMs at higher cost. And of course, PTMs do affect protein function; ignoring them would miss a core aspect of how proteins are regulated.