ENZIMAS. CONCEPTO Y ESTRUCTURA. Biocatalizador Centro activo

Summary

In this video, the concept of enzymes is explored in detail, beginning with the fundamentals of chemical reactions and their influencing factors. The speaker introduces enzymes as biocatalysts that accelerate metabolic reactions, emphasizing their specificity and role in living organisms. Enzyme structure is explained, covering both the protein component (apoenzyme) and the non-protein component (cofactor or coenzyme). The importance of the enzyme’s active site in catalyzing reactions is also highlighted, along with its two key functions: substrate binding and facilitating the reaction. This insightful lesson enhances the understanding of enzymes in biochemistry and metabolism.

Takeaways

• 😀 A chemical reaction involves the rearrangement of atoms in molecules, transforming reactants (substrates) into products.
• 😀 Chemical reactions in living organisms occur constantly, forming the basis of metabolism.
• 😀 Reactions in living organisms happen much faster than in vitro, with the aid of catalysts such as enzymes.
• 😀 The speed of a chemical reaction can be influenced by factors like substrate concentration, temperature, catalysts, surface area, agitation, and pressure.
• 😀 Temperature cannot be excessively increased in living organisms, as they can only survive within specific temperature ranges.
• 😀 Catalysts increase the reaction speed but do not participate in the reaction itself, meaning they are not consumed or changed in the process.
• 😀 Enzymes are biological catalysts, primarily proteins, which increase the rate of metabolic reactions in organisms.
• 😀 Enzymes are highly specific, each acting on a particular substrate and catalyzing a specific biochemical reaction.
• 😀 Most enzymes are proteins, although there are exceptions such as ribozymes, which are less common.
• 😀 Enzymes can be composed of both a protein part (apoenzyme) and a non-protein part (cofactor or coenzyme). Cofactors are typically metal ions, while coenzymes are organic molecules like vitamins.
• 😀 The active site of an enzyme is where the substrate binds, and it contains both a binding site (for substrate attachment) and a catalytic site (where the reaction occurs).

Q & A

What is a chemical reaction, as explained in the video?

A chemical reaction is described as a phenomenon where molecules, called reactants or substrates, undergo a reorganization of their atoms. This involves breaking and rearranging chemical bonds to form new substances, called products.

Why do chemical reactions happen faster in living organisms compared to outside them?

In living organisms, reactions occur much faster because various factors, including the presence of catalysts (like enzymes), influence the reaction rate. Outside the organism, these factors are not present, causing the reaction to take much longer.

What factors affect the rate of a chemical reaction?

The rate of a chemical reaction depends on several factors such as substrate concentration, temperature, presence of a catalyst, surface area of contact, agitation, and pressure.

Why can't temperature be increased in living organisms to speed up reactions?

Temperature cannot be increased significantly in living organisms because they operate within narrow temperature ranges that are necessary for their survival. Excessive heat can harm biological structures.

What role does a catalyst play in a chemical reaction?

A catalyst is a substance that increases the speed of a chemical reaction without being consumed or directly involved in the reaction itself. It works by lowering the activation energy needed for the reaction to occur.

What is an enzyme?

An enzyme is a biocatalyst, a type of catalyst that is organic in nature. Enzymes speed up metabolic or biochemical reactions, and each enzyme is specific to certain substrates and reactions.

How are enzymes structured?

Enzymes have a complex structure and can be composed entirely of protein or consist of a protein component (apoenzyme) and a non-protein component (cofactor or coenzyme). Cofactors are usually inorganic ions, while coenzymes are organic molecules, typically vitamins.

What is the difference between an apoenzyme and a holoenzyme?

An apoenzyme is the protein portion of an enzyme, while the holoenzyme is the complete active enzyme, consisting of the apoenzyme plus its cofactor or coenzyme.

What is the active site of an enzyme?

The active site of an enzyme is the specific region where the substrate binds. It includes a binding site, where the substrate attaches, and a catalytic site, where the reaction is facilitated, increasing the reaction speed.

What is the significance of enzymes in metabolism?

Enzymes are crucial in metabolism because they accelerate the biochemical reactions that are fundamental to life processes. Without enzymes, these reactions would occur too slowly to sustain life.