Microbiology

Microbiology Study Guide

digested, a catabolism reaction is likely to take place. In contrast, anabolism takes place when the smaller molecules are joined together through synthesis. There also exist some chemical substances known as cofactors that support the enzymes in their metabolic activities. These are the ions and molecules that are necessary to undertake the chemical reactions in an enzyme. Iron, zinc, and manganese are some instances of ions, while NAD and FAD are the coenzymes, or organic molecules, that assist the enzymes in their metabolic activities. The source of energy in the cell of the microbe is infused by the chemical substance known as adenosine triphosphate (ATP). It is often denoted as the currency for energy as it can be spent or used in order to undertake the chemical reactions. ATPs are needed by all the organisms and act as a universal energy transfer molecule. In fact, at the time of catabolism metabolic reaction, or anabolic reactions, the energy which is released is also stored in the ATP molecules. The structure of the ATP molecule constitutes of three parts: the adenine, ribose, and phosphate groups. The adenine consists of the double ring of nitrogen and carbon. Ribose is attached to this ring and is made up of a set of five carbon carbohydrates. The phosphate groups are attached to the ribose with the help of covalent bonds. ATP molecule:

The function performed by the coenzymes at the time of chemical reaction during metabolism is that of the acceptance of electrons, including passing them on to other molecules and coenzymes. When the electrons or protons are removed from the electrons, it is called oxidation . When these are added to the coenzyme, it is called reduction . This is why the set of chemical reactions occurring in the molecule is known as oxidation-reduction reactions. These reactions provide an essential source of energy to the cell metabolism. There are other molecules known as cytochromes that actively participate in this energy reaction process by accepting and releasing electrons through an electron transport system. When the electrons, rich in energy, move from these cytochromes and coenzymes, they drain this energy from the electrons and it is used to form ATP, ADP, and phosphate ions in the molecule.

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