Bio 111 lecture 17

all secondary structures are formed by what type of bonding within the peptide backbone?

h-bonding

what is tertiary structure of a protein?

the entire 3D structure of a folded protein

what is tertiary structure stabilized by?

interactions between the R groups

what are the two types of bonding possible in electrostatic interactions?

H bonds between R groups

ionic bonds between R groups

what do the SH(sulfhydryl) groups of cysteine form?

disulfide bridges

what are van der waals interactions between?

nonpolar molecules

are VDW interactions weak or strong?

weak

what causes VDW interactions?

charge fluctuations in the electron clouds of atoms

what are hydrophobic interactions?

hydrophobic R groups fold to the interior of the protein to avoid contact with the aqueous environment

what are the four types of interactions that stabilize tertiary structure?

Hydrophobic

Electrostatic

Van der waals

Disulfide bridges

what are protein domains?

subunits within a protein that carry out specific functions

can one protein contain multiple domains?

yes

what proteins need a DNA binding domain?

any protein that directly binds to DNA

what requires a transcriptional activation domain?

activating transcription of a gene to interact with RNA polymerase

what defines the function of a protein?

the domains it has

tertiary structure is the highest level of structure for _________

a single protein

what is quaternary structure?

the interaction between 2+ proteins to form a multi-protein complexwh

what is an example of quaternary structure?

hemoglobin protein in RBCs consists of 4 proteins

Proper _______ is critical to protein function

folding

what are chaperone proteins?

enzymes that help proteins fold and/or refold into the proper shape

what are the consequences of misfolded proteins?

they are unable to function properly and are the basis of certain diseases