Haemoglobin
HAEMOGLOBIN
Transition Metals In Biology
•
Coordination compounds participate in many important biological processes in plants and animals.
•
The following are such processes:
•
1. Transport and storage of oxygen
•
2. Electron transfer
•
3. Catalysis
•
4. Photosynthesis
TRANSPORT AND STORAGE OF OXYGEN
HAEMOGLOBIN
Haemoglobin, the red pigment in red blood cells carries oxygen from the lungs to the tissues. It is called the respiratory pigment.
It delivers the oxygen molecule to the myoglobin in the tissues.
Haemoglobin, a protein is an iron-porphyrin complex.
Its two H+ ions bonded to nitrogen atoms are displaced upon coordination to iron.
Complexes formed between porphine and metals are called metal porphyrines; the iron porphyrine complex is called the heme group
(prosthetic group), which is a part of haemoglobin.
A quadridentate ligand
A quadridentate ligand has four lone pairs, all of which can bond to the central metal ion.
E.g. haemoglobin
The functional part of this is an iron(II) ion surrounded by a complicated molecule called haem (heme).
Haem is a hollow ring of carbon and hydrogen atoms, at the centre of which are 4 nitrogen atoms with lone pairs on them.
Haem
Haem is one of a group of similar compounds called porphyrins.
They all have the same sort of ring system, but with different groups attached to the outside of the ring.
Each of the lone pairs on the nitrogen can form a co-ordinate bond with the iron(II) ion - holding it at the centre of the complicated ring of atoms. Structure of Haem
The Heme Group; the Defining Example of a Bioinorganic
Chip
Haemoglobin
The iron forms 4 co-ordinate bonds with the haem, but still has space to form two more - one above and one below the plane of the ring.
The protein globin attaches to one of these positions using a lone pair on one of the nitrogens in one of its amino acids.
Haemoglobin
Overall, the complex ion has a co-ordination number of 6 because the
Transition Metals In Biology
•
Coordination compounds participate in many important biological processes in plants and animals.
•
The following are such processes:
•
1. Transport and storage of oxygen
•
2. Electron transfer
•
3. Catalysis
•
4. Photosynthesis
TRANSPORT AND STORAGE OF OXYGEN
HAEMOGLOBIN
Haemoglobin, the red pigment in red blood cells carries oxygen from the lungs to the tissues. It is called the respiratory pigment.
It delivers the oxygen molecule to the myoglobin in the tissues.
Haemoglobin, a protein is an iron-porphyrin complex.
Its two H+ ions bonded to nitrogen atoms are displaced upon coordination to iron.
Complexes formed between porphine and metals are called metal porphyrines; the iron porphyrine complex is called the heme group
(prosthetic group), which is a part of haemoglobin.
A quadridentate ligand
A quadridentate ligand has four lone pairs, all of which can bond to the central metal ion.
E.g. haemoglobin
The functional part of this is an iron(II) ion surrounded by a complicated molecule called haem (heme).
Haem is a hollow ring of carbon and hydrogen atoms, at the centre of which are 4 nitrogen atoms with lone pairs on them.
Haem
Haem is one of a group of similar compounds called porphyrins.
They all have the same sort of ring system, but with different groups attached to the outside of the ring.
Each of the lone pairs on the nitrogen can form a co-ordinate bond with the iron(II) ion - holding it at the centre of the complicated ring of atoms. Structure of Haem
The Heme Group; the Defining Example of a Bioinorganic
Chip
Haemoglobin
The iron forms 4 co-ordinate bonds with the haem, but still has space to form two more - one above and one below the plane of the ring.
The protein globin attaches to one of these positions using a lone pair on one of the nitrogens in one of its amino acids.
Haemoglobin
Overall, the complex ion has a co-ordination number of 6 because the