Bacteria, why do they make me sick?/Glossary
Glossary
Antibody: molecules produced by B lymphocytes. The antibodies, (Ab) have a common basic structure. However, the antigen-binding site is specific to each of them.
Antigen: any molecule able to induce the production of specific antibodies and the activation of B lymphocytes.
B lymphocytes: are a type of lymphocytes responsible for creating or producing antibodies for a specific antigen. They can also work as antigen-presenting cells, and, eventually, they can transform into memory B Cells when activated by the interaction with an antigen.
Bacteriocins: proteins with antibacterial activity.
Complement system: This system is part of the innate immune system and is a nonspecific defense against pathogenic microorganisms. It consists of proteins called the complement. In the case of inflammatory reactions, the complements travel to the infected tissue and here, they work as a sign to attract immune system cells. They adhere to harmful bacteria to mark them as a target or they form pores in the membranes of the pathogens and cause lysis.
Eukaryote: cells that have a nucleus that contains the genetic material (DNA). They are complex and evolved cells. Inside, there are membranous organelles. This cell type can be animal or plant.
Gram’s method or Gram stain: It is a method created by Christian Gram in 1884 to distinguish and differentiate bacteria under the microscope. The first step is the application of a crystal violet stain. Then, there is the decolorization with ether and/or acetone. Gram-positive bacteria retain the first stain, causing it to look violet or dark blue under a microscope. Gram-negative bacteria become decolorized. Finally, a secondary stain (safranin) is added and Gram-negative bacteria will appear pink.
Immunological memory: it is the ability of rapid immune response against an agent that already had contact with the immune system.
Integrases: recombination enzymes that recognize short specific homologous sequences.
Interneuron: is a central nervous system neuron that interacts with other neurons exclusively, and never with sensory receptors or muscular fibers.
Lipopolysaccharides: They are the main component of the outer membrane of Gram-negative bacteria. They are the main responsible for the endotoxin shock induced by Gram-negative bacteria.
Lymphocytes: or also called white cells are the blood cells responsible for the specific defense of the immune system. They have receptors in their membranes that allow them to recognize a large variety of pathogens.
Macrophages: antigen-presenting cells. After ingesting foreign particles or antigens, the macrophages present them to the lymphocytes to begin maturation and specific immune response.
Motor neurons: neurons of the central nervous system that project their axon towards a muscle or gland.
Mucosae: is a layer of cells that secretes substances containing protective elements against pathogenic bacteria. They are present in the digestive, respiratory and urogenital tract.
Nosocomial infections: infections contracted by patients as a result of being hospitalized. They are also called hospital-acquired infection.
Palindromic sequence: is a DNA or RNA sequence arranged in a way that it reads equally from 5 ’to 3’ and from 3 ’to 5’.
Peptidoglycan: it is the main component of the bacterial cell wall. It can be defined as a structure consisting of sugars and amino acids that surrounds the cell membrane, giving structural strength.
Phylum: is the third element of classification of living beings in a taxonomic hierarchy. The first one is “Domain”, then “Kingdom”, and finally “Phylum” or “Division”. Phylum groups together all living things with the same organization system.
Prokaryote: very simple cells that lack membrane-bound organelles or nucleus. This is why the genetic material (DNA) is located in the cytoplasm. Bacteria belong to this type of microorganisms.
spp.: in general, is an abbreviation to refer to all the species of a genus.
T lymphocytes: also called T cell. They are an important type of lymphocytes that maintain the immune system and are essential to fight against pathogenic microorganisms. There are two main types of T lymphocytes, Cytotoxic T cell (Tc) and the T helper cells (Th). The Tc look for antigen infected cells in the body. When a Tc recognizes an antigen bound to a cell, it adheres to the surface of the infected cell and produces toxic molecules, killing the cell.
The Th secretes cytokines when activated by an antigen. Then, they activate B lymphocytes to begin their immune response
Transposons: Are mobile DNA fragments that can move from one chromosome to another.
Virulence factors: It refers to pathogen’s intrinsic properties that enable adhesion, invasion, and infection of the host. Adhesins are bacterial adhesion factors that enable pathogen bacteria to colonize the host’s mucus. Some components of the surface or enzymes, facilitate host cell invasion. Toxins change the physiology of the cell or the host, resulting in the appearance of the symptoms and the development of the disease.