Types of proteins Flashcards
3 examples of fibrous proteins?
collagen, keratin and elastin
an example of a globular protein?
insulin
2 examples of conjugated protein?
catalyse and haemoglobin
what are fibrous proteins?
they form long and insoluble molecules, the sequence in the primary structure is repetitive and their structures are organised
what are globular proteins?
they are compact soluble and spherical in shape
what are conjugated proteins?
they contain non-specific protein groups - prosthetic groups
why are fibrous proteins insoluble?
they have a high proportion of hydrophobic R groups in their primary structure
why are globular proteins soluble?
they fold so they are hydrophobic and the R groups are kept away from the aqueous environment
what is keratin?
it is present in hair, nails and skin and has lots of disulphide bridges so it is strong and inflexible
what is elastin?
it is found in elastin fibres present in blood vessels and alveoli. it is flexible but returns to its original shape
what is catalyse?
an enzyme that has a quaternary structure with 4 ham groups. the prosthetic group allows interaction with hydrogen peroxide to speed up reactions
what is haemoglobin?
has a quaternary structure of 2 alpha subunits and 2 beta subunits and a ham group. the iron allows it to combine reversibly with oxygen
what is insulin?
it is a soluble hormone that travels in the blood stream. the shape needs to precise
