Polypeptides Flashcards
Polypeptides
short chains of amino acids linked by peptide bonds
Extracellular matrix
non-cellular 3D macromolecule network
List the functions of extracellular matrix
- forming an essential support structure for cells
- controlling communication between cells
- segregating tissues
- regulating cell processes such as growth, migration, and differentation
List the general properties of ECM
- scaffolding
- rigid
- dense
- porous
- insoluble
- reservoir for growth factors and bioactive molecules
ECM plays significant role in _________________ and __________
cellular communication and function
General properties of ECM
- biodegradable
- biocompatible
- determines and controls behaviors of cells: proliferation, adhesion, migration, polarity, differentiation, and apoptosis
What are the 3 medical applications with the ECM?
- tissue repair
- organ transplantation
- regeneration
the ______________ step is key to improve mechanical properties after decellularization
cross-linking
Collagen is the most abundant __________ of ________ origin.
protein of animal origin
Collagen is the main structural protein found in ___________ tissue.
connective tissue; ligaments, tendons, and cartilage
Collagen provides the skin with _________ and _________
support and strength
Collagen forms the structural network of tissues such as ___________ (3)
blood vessels, bones, and cartilages
Tropocollagen contains
3 polypeptide chains wound around each other to form a single helical structure
Tropocollagen is stabilized with _______ bonding
hydrogen bonding
List the biomedical applications of collagen
- drug delivery
- ophthalmology - collagen shield
- sponges for burns/wounds
- gene delivery - nanoparticles
- hemostatic sealant
Easy modification to produce desired materials is possible by using collagens __________ groups
functional
the ____________ of amino acids of collagen allow many different chemical reactions
side chains
_________ has a strong impact on the structure of collagen
drying
__________________ hydrolysis forms gelatin
heat-induced
Collagen can be altered to form _____________ (4)
- films
- gels
- powders
- sponges
Keratin is a major component of ________ (4)
- hair
- feathers
- wool
- horns
Keratin is a ______________ structural protein made of amino acids that form a ______________ structure
fibrous structural protein; repeating structure
Keratin primarily _______ (5)
- carbon
- oxygen
- nitrogen
- hydrogen
- sulfur
Keratin protects __________ cells and strengthens certain organs
epithelial cells
Keratin plays a key role in ____________.
wound healing
Keratin is the most abundant __________________
structural protein
List the general properties of keratin
- biodegradable
- biocompatible
- insoluble in water
- chelation
- high stability
- absorbs formaldehyde
- high toughness
- high modulus
List the 5 biomedical applications of keratin
- water purification and air cleansing
- wound healing
- bone regeneration
- hemostasis
- nerve repair
what is silk fibroin and what is it composed of?
a fibrous protein made of 17 amino acids
Where does silk fibroin come from?
- cocoon silk from silkworm
- spiders
Silk fibroin is a _________ copolymer with ______________ and ___________ blocks
peptide copolymer
hydrophobic and hydrophilic blocks
the hydrophobic blocks with short amino acids form _____________ through ____________ bonding.
crystals through H bonding
Hydrophilic blocks are also with ___________ amino acids
charged
What are the 7 general properties of silk fibroin?
- durability
- biocompatible
- lightweight
- high strength
- high toughness
- elastic
- stable under thermal conditions up to 250 C
Solvent processed silk tends to ________________ than aqueous based
degrade slower
If you regulate crystallinity of silk, you can alter ____________ (4)
- degradation rate
- pore size
- porosity
- MWD
List the 4 processes for silkworm
- gas forming - develop scaffolds
- salt leaching
- electrospinning
- electro sprayings
What is the limit to processing silk?
very difficult to produce in large quantities
