Common Biochemical Reactions

1. Common Biochemical Reactions

2. chemical reaction • a process involving one, two or more substances (called reactants), characterized by a chemical change and yielding one or more product(s) which are different from the reactants

3. chemical change • molecules attaching to each other to form larger molecules, molecules breaking apart to form two, or more, smaller molecules, or rearrangement of atoms within molecules

4. chemical change • involve the making or breaking of chemical bonds • does not change the nucleus of the atom in any way, only the interaction of the electron clouds of the involved atoms • Nuclear reactions are not considered chemical reactions, although chemical reactions may follow a nuclear transformation.

5. Types of chemical reaction • Synthesis, where two or more compounds unite to form a more complex product

6. Types of chemical reaction • Chemical decomposition, where a substance is decomposed into smaller compounds; • Combustion, where a substance reacts with oxygen gas

7. Types of chemical reaction • Single displacement reaction, also called a single replacement reaction, characterized by an atom of an element which is part of a compound being displaced out of it by a more reactive atom

8. Types of chemical reaction • Double displacement reaction, also called a double replacement reaction, where compounds (usually ionic) exchange ions to form different compounds;

9. Types of chemical reaction • Acid-base neutralization, where an acid and an base react producing water;

10. Types of chemical reaction • organic reactions, which encompass several different kinds of reactions involving compounds which have carbon as the main element in their molecular structure.

11. Types of chemical reaction • redox reactions, which involve electron transference between compounds (metallic single displacement and combustion are two common examples) • acid-base reactions

12. Nucleophilic Substitution Reactions:  replacement of one  atom or group with a different nucleophilic atom or group

13. Nucleophilic Substitution Reactions:  • Generally anions or unshared electron pairs

14. Common biological nucleophiles • oxygen, nitrogen, and sulfur

15. Hydrolysis Reactions • a common class of nucleophilic substitution • Addition of water to break a covalent bond • Hydrolysis of ATP

16. Elimination Reactions • removal of atoms to form a double bond • Dehydration: removal of water (e.g. from a C - C bond to form a C = C double bond

17. Addition Reactions • combining two molecules to form a single product (generally across a C = C double bond) • Hydration:  Addition of water (e.g. to a C = C double bond) • Ex. a late step in the Krebs Cycle

18. Isomerization Reactions • intramolecular rearrangement of atoms or groups (e.g. isomerization of sugar molecules

19. Oxidation-Reduction Reactions • transfer of electrons from a donor (reducing agent) to an acceptor molecule (oxidizing agent) • Reduction: gain of electrons • gain of Hydrogen or loss of Oxygen • Oxidation:  loss of electrons • gain of Oxygen or loss of Hydrogen • Note:  Oxidation and Reduction are coupled reactions (REDOX)