Author: Anonymous

Which amino acid has a side chain that, due to its small size and lack of chirality, introduces conformational flexibility in protein loops?

A salt bridge in a protein structure is best described as:

Which of the following functional groups typically behaves as an electrophile in organic reactions?

The following is an excerpt from a recent scientific publication:“Covalent inhibitors can achieve exquisite potency and durable target occupancy through a combination of covalent and noncovalent interactions. Drugs that possess a covalent mechanism‑of‑action encompass recent blockbusters (Clopidogrel) as well as early cornerstones of modern medicine (aspirin and penicillin). Despite this well‑documented history and the advantages from sustained target engagement, pharmaceutical companies have traditionally shied away from covalent drug programs due to concerns about potential idiosyncratic toxicity. However, clinical successes over the past decade (e.g. Ibrutinib), along with improvements in technologies used throughout the drug discovery pipeline, have reignited broad interest in this class of therapeutics.” What key advantage of covalent inhibitors is emphasized here in drug discovery?

Which amino acid side chain is best suited to anchor a transmembrane helix in a lipid bilayer via hydrophobic interactions?

What is the dominant type of noncovalent interaction between the side chains of phenylalanine and tryptophan in a folded protein?

The following is an excerpt from a recent scientific publication:“In this study, we adopted the fragment‑based drug design approach … to extract noncovalent and covalent fragments according to distinct 3D interaction modes … we recombined BTK‑focused libraries, and 23 compounds within our libraries have been validated … provides valuable resources for virtual screening of covalent and noncovalent drugs targeting similar molecular targets.” For a kinase target like BTK, what is the advantage of combining covalent and noncovalent fragments in library design?

The following is an excerpt from a recent scientific publication:“We will then use this understanding of protein structure at the atomic level to describe how the precise shape of each protein molecule determines its function in a cell. Proteins are therefore known as polypeptides. Each type of protein has a unique sequence… We start this paper by considering how the location of each amino acid… determines its three‑dimensional shape… precise shape of each protein molecule determines its function in a cell.” What essential principle is emphasized by this excerpt?

Which structural feature most directly explains cooperativity in hemoglobin but not in myoglobin?

Which statement about DNA strands is correct?