Two-component system regulating response to low Gln,

a) Glutamine dissociates from the sensor domain in the NtrB protein, leading to activation of a histidine kinase transmitter domain in NtrB

b) glutamine binds to a sensor domain of NtrB, causing a conformational change in the protein that inhibits its histidine kinase activity, the regulatory domain of NtrC blocks its DNA-binding domain from binding the glnA enhancers.

c) Activated transmitter domain of NtrB that transfers the γ-phosphate of ATP to a histidine residue (H), this phosphohistidine then transfers the phosphate to an aspartic acid residue (D) in the NtrC protein

d) This causes a conformational change in NtrC that unmasks the NtrC DNA-binding domain so that it can bind to the glnA enhancers

Which of the following combination is correct?

#Question id: 742

#Unit 1. Molecules and their Interaction Relevant to Biology

Match the following

#Question id: 741

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of following statements are INCORRECT about secondary structure of proteins

A. Long block of Glu residues segment of the chain will not form an alpha helix at pH 7.0 but it ll take helical confirmation below its pKR value

B. Long block of Lys residues segment of the chain will not form an alpha helix at pH 7.0 but it ll take helical confirmation above its pKR value

C. Long block of Ala residues segment of the chain will not form an alpha helix at pH 7.0 but it ll take helical confirmation below its pKR value

D. Histidine side chain remain uncharged over pH range 3-6

#Question id: 740

#Unit 1. Molecules and their Interaction Relevant to Biology

The conformation of the backbone of a polypeptide is described completely by the angle(s) of rotation about which bond(s)?

#Question id: 739

#Unit 1. Molecules and their Interaction Relevant to Biology

What is true about the rotation about bonds in a protein backbone?

#Question id: 738

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following is correct for peptide bonds

A) C and N are shorter than typical C-N bonds.

B) C and N are longer than typical C-N bonds.

C) C and O are longer than typical C=O bonds.

D) C and O are shorter than typical C=O bonds.

#Question id: 737

#Unit 1. Molecules and their Interaction Relevant to Biology

Which structure below indicates the proper hydrogen-bonding pattern between amino acids in an α-helix? (Dashed lines represent the hydrogen bonds.)