Biochemistry · MU Sofia

7. Characteristics of Enzymes

Covers the defining characteristics of enzymes as biological catalysts: specificity, efficiency, regulation and reusability. Explains coenzymes and prosthetic groups with examples, the -ase naming convention and the Enzyme Commission classification into six reaction classes, then outlines the catalytic mechanism, the enzyme-substrate complex and active site, and substrate, stereochemical and reaction specificity. Ends with three multiple-choice questions and their answers.

Inside: 8 sections · 2 labelled pictures · 10 flashcards · 3 min

Topic 7 of 70 in the MU Sofia syllabus for Biochemistry (Dental Medicine, Year 2). The free AceMed note covers it in 8 sections, about 477 words (3 min of reading), with 10 flashcards.

In this note

  1. Characteristics of Enzymes as Biological Catalysts
  2. Coenzymes and Prosthetic Groups
  3. Nomenclature and Classification of Enzymes
  4. Mechanism of Enzyme Catalysis
  5. Enzyme-Substrate Complex and Active Site
  6. Enzyme Specificity
  7. MCQ ☺
  8. Answers

Characteristics of Enzymes as Biological Catalysts

  • Enzymes are biological catalysts that accelerate chemical reactions within cells by lowering the activation energy required for the reaction to occur. Key characteristics of enzymes include:
  1. 1. Specificity: Enzymes exhibit high specificity for their substrates, meaning they catalyze specific reactions involving specific substrates.
  2. 2. Efficiency: Enzymes significantly increase the rate of reaction without being consumed in the process, making them highly efficient catalysts.
  3. 3. Regulation: Enzyme activity can be regulated by various factors such as pH, temperature, substrate concentration, and allosteric effectors.
  4. 4. Reusability: Enzymes can catalyze multiple rounds of reactions and are not altered or consumed during the process.

Coenzymes and Prosthetic Groups

  • Coenzymes: Coenzymes are organic molecules that assist enzymes in catalysis by carrying chemical groups between enzymes. Examples include NAD+, FAD, and coenzyme A.
  • Prosthetic Groups: Prosthetic groups are non-protein molecules that are tightly bound to enzymes and are essential for their catalytic activity. Examples include heme in catalase and flavin mononucleotide (FMN) in succinate dehydrogenase.

Continue reading free

The whole note, all 8 sections, is free with an AceMed account, with its 10 flashcards. Premium adds flashcard recall, highlights and Ask AI.