Protiens Flashcards
(30 cards)
What are proteins?
Proteins are large sized macromolecules having one or more polypeptides (chains or polymersof AA linked by peptide bond)
To qualify as a protein, a polypeptide must have at least 50 amino acid.
Why is protein a heteropolymer?
there are only 20 types of AA
But to qualify as a proteins a polypeptide must have at least 50 AA.
What is a homopolymer?
It has only one monomer repeating n times
What is the most abundant tissue in the animal world? Why?
Collagen. Main competent of connective tissue of animals.
What is the most abundant protein in the whole biosphere?
Rubisco
Ribulose biphosphate carboxylase oxygenase
It is the enzyme involves in C fixation (photosynthesis)
A process in which co2 is converted by plants into energy rich molecule glucose
What are different types of protein structures?
Primary, secondary, tertiary, quaternary
What is Primary structure?
The sequence in which AA are arranged in a polypeptide chain of protein
Gives positional information of AA
Where are first and last AA positioned in proteins? What are they called respectively?
First AA
present on left end
N-terminal
Last AA
Right end
C-terminal
What are types of secondary structures?
Some portion of protein thread are folded in form of helix or pleated sheet
Alpha helix and beta pleated sheet.
Where and how does interaction take place in alpha helix?
Between every fourth AA by formation of intermolecular H2 bond
What is intramolecular H2 bond?
Bond formed between H2 and highly electronegative ago such as N,O,F of same molecule
What kind of helices are observed in Proteins? Example?
Right handed helices
Example
Keratin
Present in hair
How is beta pleated sheet formed?
When two or more polypeptide chains are held together by intermolecular hydrogen bond
How is H2 bond different in Helix and pleated sheet?
Intra and inter
Electronegative atom of same molecule
Different molecule
Respectively
What is a collagen helix?
The polypeptide coil of collagen helix in strengthened by establishing hydrogen bind and locking effect also occurs with help of AA, proline, hydroxyproline
What is a tertiary protein? Example?
Long protein chain or polypeptide chain that folds upon on itself like a hollow woollen ball.
It gives 3 dimensional view of a protein
Myoglobin
What is a subunit?
Individual polypeptide chains of quaternary proteins
What is a quaternary protein?
Formed when a protein has one or more subunits or polypeptide chains and each polypeptide has a primary, S, T structure of it’s own.
What gives architecture of Q protein?
The way folded polypeptides are arranged with respect to each other
Example and structure of a Q protein?
Heemoglobin
Four polypeptide chains
2 alpha and 2 beta
What are 6 functions of proteins?
Enzymes
Defence protein
Hormone
Receptor
Tramsport protien
collagen
How do proteins form enzymes? Example?
All enzymes except few are built up of proteins alone or in conjugation with some non protein materials called co factors
Trypsin in pancreatic juice
