Term
| primary structure of a protein |
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Definition
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Term
| secondary structure of a protein |
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Definition
| 3D structure resulting from a regular pattern of H bonds between the CO and NH components of the amino acids in the polypeptide chain |
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Term
| tertiary structure of a protein |
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Definition
| occurs when the R groups of the amino acids bond with one another |
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Term
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Definition
| seems to be proteins working with each other |
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Term
| the bond between 2 amino acids |
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Definition
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Term
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Definition
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Term
| how a peptide bond is formed |
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Definition
| by linking the a-carboxyl group of one amino acid to the a-amino group of the other |
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Term
| depiction of how a peptide bond is formed |
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Definition
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Term
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Definition
| each amino acid unit in a polypeptide chain |
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Term
| the directionality of a polypeptide chain |
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Definition
| has a-amino group at one end and a-carboxyl group on the other end |
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Term
| the end that's taken to be the beginning of the polypeptide chain |
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Definition
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Term
| general structure of a polypeptide chain |
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Definition
C-N backbone with carbonyl groups and side chains, as shown here
[image] |
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Term
| the most common cross-linking that occurs in polypeptide chains |
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Definition
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Term
| why it's important to know amino acid sequences |
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Definition
1: sequence determines structure
2: knowledge of sequence is essential to elucidating its function
3: alterations in sequence can produce abnormal functions and disease
4: sequence of a protein can reveal something about its evolutionary history |
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Term
| what determines 3D structure of a protein? |
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Definition
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Term
| what determines function of a protein? |
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Definition
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Term
| are peptide bonds in proteins cis or trans? |
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Definition
| almost all of them are trans |
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Term
| why do peptide bonds prefer trans configuration? |
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Definition
| because there's steric clash between the R groups in cis configuration |
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Term
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Definition
| the fact that 2 atoms can't be in the same place at the same time |
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Term
| what steric exclusion does for proteins |
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Definition
| restricts the number of possible peptide conformations |
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Term
| some types of structures that occur in a protein's secondary structure |
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Definition
-a-helices
-B pleated sheets
-turns |
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Term
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Definition
| coiled structure stabilized by intrachain H bonds |
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Term
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Definition
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Term
| the a-helix is stabilized by... |
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Definition
| H bonds between the NH and CO groups of the main chain |
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Term
| are a-helices right or left handed? |
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Definition
| essentially all right handed |
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Term
| how B sheets are stabilized |
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Definition
| stabilized by H bonding between polypeptide strands |
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Term
| structure of a single polypeptide B strand |
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Definition
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Term
| structure of polypeptide B strands H bonded to each other |
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Definition
[image]
the top is antiparallel and the bottom is parallel |
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Term
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Definition
| H bonding between 2 or more B strands |
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Term
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Definition
| can be almost flat, but most adopt an almost twisted shape |
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Term
| polypeptide chains can change direction by... |
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Definition
| making reverse turns and loops |
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Term
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Definition
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Term
| the compact globular shape of most proteins requires this of their polypeptide chains |
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Definition
| reversals in the direction |
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Term
| where the turns and loops in polypeptide chains are in proteins |
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Definition
| on the surface of the proteins |
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Term
| function of fibrous proteins |
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Definition
| provide structural support for cells and tissues |
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Term
| ther general structure of fibrous proteins |
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Definition
| mostly extensive stretches of secondary structure |
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Term
| examples of fibrous proteins |
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Definition
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Term
| depiction of a fibrous protein |
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Definition
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Term
| 2 ways intertwined strands in fibrous proteins can be stabilized |
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Definition
-H bonding inside
-steric repulsion outside |
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Term
| the only residue that can fit in an interior position in a protein helix |
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Definition
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Term
| the interior of the triple-stranded helical cable that forms collagen |
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Definition
| very crowded; only glycine can fit in there |
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Term
| tertiary structure is caused by... |
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Definition
| interactions between R groups |
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Term
| protein with tertiary structure |
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Definition
| has a compact, 3D structure |
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Term
| the type of protein that performs most of the chemical transactions in the cell |
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Definition
| compact, globular proteins with specific 3D structure |
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Term
| how a protein folds in an aqueous environment |
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Definition
folds such that the hydrophobic parts are on the inside and the hydrophilic parts are on the outside
driven by the hydrophobic effect |
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Term
| how proteins that span the biological membrane, such as porins, are arranged |
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Definition
-hydrophobic and hydrophilic on inside
-outside interacts with hydrophobic environment and inside permits a channel of water |
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Term
| motif or supersecondary structure |
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Definition
| some combinations of secondary structure |
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Term
| the tertiary structure of many proteins can be divided into... |
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Definition
| structural and functional units |
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Term
| subunit (in the context of proteins) |
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Definition
| polypeptide chain in a protein that consists of more than 1 polypeptide chain |
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Term
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Definition
| multiple polypeptide chains working together as a single unit |
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Term
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Definition
protein that doesn't have its characteristic shape
randomly coiled peptide without its normal activity |
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Term
| the mpost stable structure of a protein |
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Definition
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Term
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Definition
| proteins that prevent other proteins from tangling with each other, something like that |
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Term
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Definition
| protein correctly folds much quicker than it would if it randomly tried every single possibility |
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Term
| one way proteins make themselves fold more correctly |
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Definition
| by retaining partly correct intermediates, which are slightly more stable than unfolded regions |
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Term
| stability of correctly folded proteins |
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Definition
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Term
| mechanism by which proteins fold |
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Definition
| by progressive stabilization of intermediates |
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Term
| intrinsically unstructured proteins (IUP's) |
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Definition
| proteins that lack 3D structure under physiological conditions |
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Term
| advantage of a protein being able to assume different shapes |
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Definition
| versatility, being able to interact with different partners and yield different biochemical functions |
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Term
| intrinsically unstructured proteins (IUP's) appear to be important for... |
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Definition
| signaling and regulatory pathways |
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Term
| when intrinsically unstructured proteins (IUP's) assume a defined structure |
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Definition
| when they interact with other proteins |
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Term
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Definition
| proteins that appear to exist in an ensemble of approx equal energy that are in e'librium |
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