Properties of enzyme

Posted: October 4, 2009 in Kedokteran
Tags: , , , ,

Properties of enzyme by Tiara Ayu Murti.pptx

DEFINITION OF ENZYME
-Biologic polymers that CATALYZE the chemical reaction
-Protein CATALYSTS for chemical reaction in biologic system
-Specialized protein that function in the ACCELERATION of chemical reaction
-Protein CATALYSTS that increase the rate of the reaction without being changed in the overall process

CHARACTERISTICS OF ENZYME
-Not being changed in the overall process
-Selective catalysts
-Specific catalyst
-Can convert non chiral substrate into the chiral substrate
-Biological catalyst
-Act at low concentration
-Increase rate of reaction
-Most metabolic enzyme reaction are reversible

STRUCTURE OF ENZYME
Apoenzyme: The protein component of an enzyme separable from the prosthetic group but requiring it to form the functioning compound (haloenzyme)

Haloenzyme: an enzyme that has all component parts including apoenzyme and cofactors

Active Site :
– Contain the amino acid side chain that have three dimensional surface complementary to the substrate
– the part of an enzyme in which the substrate binds an at which the reaction takes place

THE INTERACTION BETWEEN ENZYME AND SUBSTRATE
-Fischer Lock and Key Hypothesis:
The active site has rigid structural features which are complementary to the substrate

– Koshland Induced Fit Hypothesis:
The active site is flexible, possessing a structure complementary to that of substrate only when the substrate is bound to the enzyme

NOMENCLACTURE
-Describe the type of reaction catalyzed
-Followed by suffix –ase
-Modification of naming indicate the substrate, the source of the enzyme and its regulation Example: xanthine oxidase, pancreatic ribonuclease

KINETICS OF ENZYME
Kinetic is: The study of reaction rates and the factors influencing them
All kinetic is based on: the law of mass action
It states: the rate of reaction is proportional to the concentration of each reactant

The Rate
The Michaelis Menten equation:
V = {Vmax . [S]}/{[S] + Km}
V : Observed velocity at given substrate concentration
Km : Michaelis Constant expressed in units of concentration (Mol/liter)
Vmax : The maximum velocity at saturating concentration substrate

Assumption that make those equation:
– Relative concentration of E and S
– Steady State assumption

Enzyme in clinical diagnosis
Plasma enzymes classified by:
1. Relatively small group of enzyme : actively secreted into the blood (e.g. zymogen for blood coagulation)
2. A Large number of enzyme species are released from cells during normal cell turnover

Clinical diagnosis:
1. Alteration of plasma enzyme levels in disease states
2. Plasma enzyme as diagnostic tools
3. Isoenzyme and diseases of the heart

Alteration of plasma enzyme levels in disease state
Plasma enzyme as diagnostic tools
Isoenzymes and disease of the heart

Comments
  1. nulisnulisnulis says:

    tetep berjuang sist jgn seperti saya yang saat ini begitu ‘futur’ karena beban akademis…jgn peduliin kata org..kalo yakin ya just do it…hahahaha,,,bahasa apaan tuh….kangeeeennn aksi bareng!!!!!

  2. nulisnulisnulis says:

    nyiaaaahhhhaaa….udah gaya2 salah kamar gw……ckckck…

  3. seisyuhada says:

    ahaha.. pasti mau komen ke aksi kan maksutnya?? ya ampun gan…ckckck
    kacamata udah setebel itu juga…

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