Theory of island biogeography

TLS Online TPP Program

#Id: 4333

#Unit 1. Molecules and their Interaction Relevant to Biology

About 75% of the charged residues in proteins are members of ion pairs that are located mostly on the protein surface.

Despite the strong electrostatic attraction interactions contribute little to the stability of a native protein.

TLS Online TPP Program

#Id: 4356

#Unit 1. Molecules and their Interaction Relevant to Biology

The overall probability of RNase A re-forming its four native disulfide links at random is-

TLS Online TPP Program

#Id: 4385

#Unit 1. Molecules and their Interaction Relevant to Biology

Proteins fold to their native conformations via directed pathways rather than stumbling on them through random conformational searches.

TLS Online TPP Program

#Id: 8749

#Unit 1. Molecules and their Interaction Relevant to Biology

Intrinsically disordered proteins lack a hydrophobic core, and have high densities of charged amino acid residues such as Lys, Arg, and Glu. Pro residues are also prominent, as they tend to disrupt ordered structures.

TLS Online TPP Program

#Id: 8750

#Unit 1. Molecules and their Interaction Relevant to Biology

The lack of an ordered structure can facilitate a kind of functional promiscuity, allowing one protein to interact with multiple partners. Some intrinsically disordered proteins act to inhibit the action of other proteins by an unusual mechanism: wrapping around their protein targets.

TLS Online TPP Program

#Id: 8751

#Unit 1. Molecules and their Interaction Relevant to Biology

The protein p27 is intrinsically disordered. It wraps around and inhibits the action of several enzymes called protein kinases that facilitate cell division.