WASp activation requires two signals (This type of two-signal input, called coincidence detection):

1. regulatory phospholipid PIP2

2. small GTP-binding protein Cdc42

TLS Online TPP Program

#Id: 8762

#Unit 1. Molecules and their Interaction Relevant to Biology

Thermostable proteins have such a high incidence of salt bridges.

TLS Online TPP Program

#Id: 8763

#Unit 1. Molecules and their Interaction Relevant to Biology

Thermophilic proteins have increased amounts of Arg, increased occurrence of Ala in helices, and Gly/Ala substitutions (which affect the entropy of the denatured state, and thus its free energy) and increased number of salt bridges. 

TLS Online TPP Program

#Id: 8764

#Unit 1. Molecules and their Interaction Relevant to Biology

Some thermostable proteins are stabilized by an increased size of the protein’s hydrophobic core, an increased size of the interface between its domains and/or subunits, and a more tightly packed core as evidenced by a reduced surface-to-volume ratio.

TLS Online TPP Program

#Id: 8765

#Unit 1. Molecules and their Interaction Relevant to Biology

Disulfide bonds are believed to increase the stability of the native state by decreasing the conformational entropy of the unfolded state due to the conformational constraints imposed by cross-linking (i. e. decreasing the free energy of the unfolded state).  

TLS Online TPP Program

#Id: 8766

#Unit 1. Molecules and their Interaction Relevant to Biology

Most protein have "loops" introduced by disulfides of about 15 residues

TLS Online TPP Program

#Id: 8767

#Unit 1. Molecules and their Interaction Relevant to Biology

Guanidinium ion and urea are chaotropic agents which disrupts hydrophobic core of proteins.