BIO-INORGANIC CHEMISTRY METALS IN BIOLOGICAL SYSTEM LESSON-1 TARUN ROY
CONTENTS Essential and non-essential elements in biological system. Metals and corresponding their metallo proteins and functions. . Metal Enzymes and their functions. * Supra-molecular chemistry (Guest-Host mechanism, Cryptand, Rotaxane, Calixarene)
*Hemoglobin (Hb) and Myoglobin(Mb) , oxygen binding and oxidation states of the metals in oxy as well as deoxy form. . Bohr effect, Co-operativity effect, Hill equation, Hematin formation,Picket-Fence porphyrin model. * Siderophores and Ionophores.
Metallo-proteins containing Cu: (Hemocyanin, Super-oxide dismutase,.) Types of Cu present in metallo-proteins [Cu(I)/Cu(II)/Cu(III)]and [Cu(A)/Cu(B)/Cu(Z)] Hemocyanin, Tyrosinase, Hemerythrin. Vitamin B12. Cu-Zn Super-oxide dismutase, Carbonic Anhydrase.
Iron-Sulfur proteins Cytochromes (a,b,c) , Cytochrome P-450 Sodium-Potassium pump. Diseases Caused by the metals.
ESSENTIAL AND NON-ESSENTIAL ELEMENTS * According to Epstein (1972), there are two main criteria to judge essentiality of an element for plant: (i) "An element is essential if the plant cannot complete its life cycle (i.e., form viable seeds) in the absence of that element" 93 (ii) "An element is essential if it forms part of any molecule or constituent of the plant that is itself essential for the plant" (for instance N in proteins and Mg in chlorophylls)
OIt is now known that the following 17 elements are essential for majority of the plants: C, H, O, N, P, K, Ca, S, Mg, Fe, Mn, Zn, B, Cu, Ni, CI and Mo. Besides these Al, Si, Se, Na, Co, V and Ga may be essential for some plants. (1) Major Elements (Macronutrients): The essential elements which are required by the plants in comparatively large amounts (1000 mg or more/kg of dry matter) are called as major elements or macronutrients. They are: C, H, O, N, P, K, Ca, S, Mg.
(2) Minor Elements (Or Micronutrients or Trace Elements): The essential elements which are required in very small amounts (less than 100 mg/kg of dry matter) or traces by the plants are called as minor elements or micronutrients or trace elements. They are: Fe, Mn, Zn, B, Cu, Ni, CI and Mo Trace elements should not be confused with the tracer elements. Tracer elements are usually radioactive or heavy isotopes which are used to trace out some metabolic pathway. Some examples of commonly used tracer elements in plant physiology are 4C, 15N, 180, 32P, 35S, 42K and45Ca
I have done M. Sc in Chemistry from IIT Hyderabad and I qualified IIT JAM 2016, CSIR NET dec2017, CSIR JRF June 2019 and GATE 2018, 2019.