Haemoglobin Structure

Haemoglobin

Its a major protein of erythrocytes (RBC) and it carries oxygen throughout the body

Chromoprotein

Give the red cell its reddish color and its composesd of heme group

Molecular dalton weight

64,450

Globular protein

protein folded into compact, rougly spherical shape

2 types of protein

Globular and linear

Globular Protein

(function) Usually perfrom transporting structure

Linear Protein

(Structural) Provide support amd strength

HB carry

HB carry O2 from lungs to the tissue and CO2 carry from ttise to the lungs

Large complex protein consists of

haem 3% and globin 97%

Haem group consist of

Porphyrin ring and ferrous iron

Globin Chains (amino acid) consists of

2 Alpha chains adn 2 non alpha chains

Heme/Globin process

heme/globin produced seperately to develop RBC, but production rate coordination are same/ balance to ensure effiencient haemoglobin assembly.

Tetramer (4)

globin chins with each heme group, twisted togtehr t expose exterior of molecule

Protoporphyrin

ring shape structure

Ferrous iron (Fe+2)

iron enter the body trhough diet, absorbed stomach then developed to the BM by transferrin erythroblast mitochrondria

Synthesis of Protoporphyrins

starts in mitochrondria of RBC precursors, where glyccrine adn succinyl CoA combine with help of ALA synthase and vitamin B6 to produce ALA

ALA

Aminolevulinic acid

Haem pocket

provides hyddrophobic environmennt protects haem molcule (iron)

Fe +2

bind oxygen so if ferrious atom contained water, it will oxidised to ferric atom and this reaction is irreversible, ferrice atoom will not transport O2

Mathaemoglobinanemia

condition where iron in haemoglobin changes from its normal form, fe2 - fe3 so hemo cant carry oxygen normally

Causes of methaemoglobinaemia

Abnormal hb-m, Enzyme defiency, toxic substance

Globin chains

protein part of haemoglobin and made by ribosomes to develop RBC and reticulocyte

Alpha chains contains

141 amino acid α and ζ

Non alpha chains

146 amino acid and β, δ, ϒ , and Є

Alpha

α

Zeta

ζ

Epsilon

ε

Beta

β

Gamma

γ

Delta

δ

Human normally carry __ functional globin genes, arranged in two dupplicate gene cluster

8

(alpha) A like cluster

short arm of chromose 16

(Beta) B like cluster

short arm of chromosome 11

α β γ δ ε ζ

6 different types of globin chains

chains are ____ with different non a chains to form different types of haemoglobin

combined

types are found in the blood at different stage of development

various

global geens are arranged on chromosomes order and are activated during different satges of development

arranged, activated

Usually only present in the yolk sac erythroblasts

Embryonic Haemoglobins

after birth, Gamma chains are largely replced by Beta chains

3 - 6 months

Hb A

two alpha and beta and 96 - 98 %

Hb A 2

two alpha and delta and 1.5- 3.2 %

Hb F

two alpha ang gamma 0.5 - 0.9%

Regulation of hb synthesis

when our body doesnt get enough oxygen the kidney produce more erthropoietin (EPO) bone marrow make more RBC/Haemoglobin to carry oxygen

hypoxia

when our body doesnt get enough oxygen