week 12 Flashcards
(17 cards)
What is a biological ligand?
a biomolecule that complexes to a metal ion to serve a biological purpose
What is cis-platin?
a coordination complex used to treat various types of cancers
What is haemocyanin?
a protein containing copper found in molluscs and anthropods that carries oxygen around the body
What is haemoglobin?
a protein contain iron found in vertebrates that transports oxygen around the body
What is a metalloprotein?
a protein that contains a metal ion cofactor
What is myoglobin?
a protein containing iron that carries and stores oxygen in the muscle cells
What is a prosthetic group?
a nonprotein group forming part of or combined with a protein
eg metal protein
macrocyclic
How many polypeptide chains does haemoglobin contain?
Four
How many polypeptide chains does myoglobin contain?
one
How is the haem group connected to the Fe ion?
It is connected via a histidine nitrogen
Does deoxy-Mb have high-spin or low-spin?
High-spin
Does oxy-Mb have high- or low-spin?
Low-spin
What state is the oxygen in when it binds to the Fe?
Superoxide
What is the active site of haemocyanin made of?
Two Cu(I) centers coordinated to three histidine residues each
side chain effectivnes with transtion metals
Side chains that contain N, O or S atoms (that have a lone pair of electrons) make excellent ligands for first row transition metals.
the different side chain functionalities (in blue) can provide a variety of coordination sites to different metals.
carboxylic acid and amine group on the α-carbon do not form a coordination bond to a metal,
Platinum in Medicine
Cisplatin is a platinum anti-cancer agent
also square-planar complex which gets its name from the cis-arrangement of its ligands
The cisplatin then binds to DNA bases and prevents transcription of that strand.
cis - patin DNA base perfernces
preferes A and G over C and T
BUT G over a because can form a stronger bond
