globular protein Flashcards
what are globular proteins
amino amino acid polypeptide chain fold into shapes that resemble sphere
what are the peculiarities of globular protein
increased solubility
polar grp on the protein surface
hydrophobic grp in the interior
what are the two terms used to describe a folding pattern
motif (fold) domain
what is motif
is a recognizable folding pattern involving two or more elements of secondary structure and connection between them
give examples of motif
β--β loop motif (alpha)
β barrel motif (like barrel shape).
for describe which type of protein folding we use fold
more complex folding pattern
example for folding pattern protein
arrangement of eight alpha helices in myoglobin - globin fold
what is domain
part of poly peptide chain that is independently stable or could undergo movement as a single entity with respect to the entire protein
how many domain does myoglobin have
one
when proteins are said to be in same protein family
similarity in primary structure and or with similar tertiary structure and function
two or more protein families that have little similarities in primary structure but display the same major structural mofit are grouped together in
super family
hemoglobin contains
four polypeptide chain with one heme prosthetic group each
iron atoms are in the ferrous state
the protein portion of Hb globin consist of
2 alpha chain ( 141 residues each) 2 beta chain ( 146 residues each)
Hb can be described as what on basis of alpha and beta
tetramer or dimer of alpha beta protomer
how many heme grp does a Hb contain and how many oxygen it can carry
4 heme grp and 4 oxygen
heme contains
4 nitrogen atom
1 iron cataion ferrous (Fe2+)
how is iron hold in heme structure
bound in the middle of tetrapyrrole skelet by 6 coordinate covalent bond
what are the other name of heme
metaloporphyrine
cyclic tetrapyrrole
what is the coordination no of iron in heme
6
what are the examples of heme protein
hemoglobin
myoglobin
cytochromes
change in po2 modulate
Hb’s affinity
what is bohr effect
right shift of saturated curve
what cause bohr effect
H+ ions
high CO2
