Bacteria are economically important as these microorganisms are used by humans for many purposes. The beneficial uses of bacteria include the production of traditional foods such as yogurt, cheese, and vinegar. Microbes are also important in agriculture for the compost and fertilizer production.
Sourdough bread is made to rise by fermentation, with a leaven that consists of bacteria, often combined with wild yeast enzymes.The milk-souring bacterial genus Lactobacillus is used to make yogurt and cheese. Bacteria are used, too, to form organic acids in pickles and vinegar.
Biotechnology involves the use of microorganisms including bacteria and fungi in the manufacturing and services industries. These include chemical manufacturing such as ethanol, acetone, organic acid, enzymes, and perfumes. Bacteria are important in the production of many dietary supplements and pharmaceuticals. For example, Escherichia coli is used for commercial preparation of riboflavin and vitamin K.E. coli is also used to produce D-amino acids such as D-p-hydroxyphenylglycine, an important intermediate for synthesis of the antibiotic amoxicillin.
Genetic engineering is the manipulation of genes. It is also called recombinant DNA technology. In genetic engineering, pieces of DNA (genes) are introduced into a host by a variety of techniques, one of the earliest being the use of a virus vector. The foreign DNA becomes a permanent feature of the host, and is replicated and passed on to daughter cells along with the rest of its DNA.Bacterial cells are transformed and used in production of commercially important products. Examples include production of human insulin (used to treat diabetes) and human growth hormone (somatotrophin used to treat pituitary dwarfism).
Bacteria such as Clostridium butyricum are used to separate fibres of jute, hemp and flax in the process of retting. The plants are immersed in water and when they swell, inoculated with bacteria which hydrolyze pectic substances of the cell walls and separate the fibres. Alternatively, the plants are spread out on the ground, where they become wetted by dew and ret naturally. These separated fibres are used to make ropes, sacks etc.
Bacteria can also be used in the place of pesticides in biological pest control. This commonly uses Bacillus thuringiensis (also called BT), a Gram-positive, soil-dwelling bacterium. This bacterium is used as a Lepidopteran-specific insecticide under trade names such as Dipel and Thuricide. Because of their specificity, these pesticides are regarded as environmentally friendly, with little effect on humans, wildlife, pollinators, or other beneficial insects.
Bacteria can be used to remove pollutants from contaminated water, soil and subsurface material.During the Mega Borg Oil Spill, for example, 100 pounds of bacteria were sprayed over an acre of the oil slick to break down the hydrocarbons present into more benign by-products.
Bacteria living in the gut of cattle, horses and other herbivores, for example Ruminococcus spp., help digest cellulose by secreting the enzyme cellulase.This is how herbivores are able get the energy they need from grass and other plants.
Also, Escherichia coli , part of the intestinal microbiota of humans and other animals, converts consumed food into vitamin K2. This is absorbed in the colon and, in animal models, is sufficient to meet their daily requirement of the vitamin.
Some bacteria are harmful and act either as disease-causing agents (pathogens) both in plants and animals, or may play a role in food spoilage.
Bacteria cause a wide range of diseases in humans and other animals. These include superficial infections (eg. impetigo),systemic infections (eg. typhoid fever), acute infections (eg. cholera) and chronic infections (eg. tuberculosis).
Plant diseases caused by bacteria are commercially important worldwide for agriculture. Besides bacterial pathogens that are already established in many areas, there are many instances of pathogens moving to new geographic areas or even the emergence of new pathogen variants. In addition, bacterial plant pathogens are difficult to control because of the shortage of chemical control agents for bacteria.
Saprotrophic bacteria attack and decompose organic matter. This characteristic has posed a problem to mankind as food such as stored grains, meat, fish, vegetable and fruits are attacked by saprotrophic bacteria and spoiled. Similarly milk and products are easily contaminated by bacteria and spoiled.
Escherichia coli, also known as E. coli, is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus Escherichia that is commonly found in the lower intestine of warm-blooded organisms (endotherms). Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in their hosts, and are occasionally responsible for product recalls due to food contamination. The harmless strains are part of the normal microbiota of the gut, and can benefit their hosts by producing vitamin K2, (which helps blood to clot when you have a cut to form a scab) and preventing colonisation of the intestine with pathogenic bacteria, having a symbiotic relationship. E. coli is expelled into the environment within fecal matter. The bacterium grows massively in fresh fecal matter under aerobic conditions for 3 days, but its numbers decline slowly afterwards.
A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular polymeric substances (EPS). The cells within the biofilm produce the EPS components, which are typically a polymeric conglomeration of extracellular polysaccharides, proteins, lipids and DNA. Because they have three-dimensional structure and represent a community lifestyle for microorganisms, they have been metaphorically described as "cities for microbes".
Escherichia coli O157:H7 is a serotype of the bacterial species Escherichia coli and is one of the Shiga toxin–producing types of E. coli. It is a cause of disease, typically foodborne illness, through consumption of contaminated and raw food, including raw milk and undercooked ground beef. Infection with this type of pathogenic bacteria may lead to hemorrhagic diarrhea, and to kidney failure; these have been reported to cause the deaths of children younger than five years of age, of elderly patients, and of patients whose immune systems are otherwise compromised.
Plant pathology is the scientific study of diseases in plants caused by pathogens and environmental conditions. Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants. Not included are ectoparasites like insects, mites, vertebrate, or other pests that affect plant health by eating of plant tissues. Plant pathology also involves the study of pathogen identification, disease etiology, disease cycles, economic impact, plant disease epidemiology, plant disease resistance, how plant diseases affect humans and animals, pathosystem genetics, and management of plant diseases.
Virulence is a pathogen's or microbe's ability to infect or damage a host.
Lipopolysaccharides (LPS), also known as lipoglycans and endotoxins, are large molecules consisting of a lipid and a polysaccharide composed of O-antigen, outer core and inner core joined by a covalent bond; they are found in the outer membrane of Gram-negative bacteria.
Foodborne illness is any illness resulting from the spoilage of contaminated food, pathogenic bacteria, viruses, or parasites that contaminate food, as well as toxins such as poisonous mushrooms and various species of beans that have not been boiled for at least 10 minutes.
Raw veganism is a diet that combines the concepts of veganism and raw foodism. It excludes all food and products of animal origin, any food that is processed or altered from its natural state, and food cooked at high temperatures. Little is known about the raw vegan diet as it is not widely practiced.
Adhesins are cell-surface components or appendages of bacteria that facilitate adhesion or adherence to other cells or to surfaces, usually the host they are infecting or living in. Adhesins are a type of virulence factor.
Lysogeny, or the lysogenic cycle, is one of two cycles of viral reproduction. Lysogeny is characterized by integration of the bacteriophage nucleic acid into the host bacterium's genome or formation of a circular replicon in the bacterial cytoplasm. In this condition the bacterium continues to live and reproduce normally. The genetic material of the bacteriophage, called a prophage, can be transmitted to daughter cells at each subsequent cell division, and at later events can release it, causing proliferation of new phages via the lytic cycle. Lysogenic cycles can also occur in eukaryotes, although the method of DNA incorporation is not fully understood.
Dickeya dadantii is a gram-negative bacillus that belongs to the family Pectobacteriaceae. It was formerly known as Erwinia chrysanthemi but was reassigned as Dickeya dadantii in 2005. Members of this family are facultative anaerobes, able to ferment sugars to lactic acid, have nitrate reductase, but lack oxidases. Even though many clinical pathogens are part of the order Enterobacterales, most members of this family are plant pathogens. D. dadantii is a motile, nonsporing, straight rod-shaped cell with rounded ends. Cells range in size from 0.8 to 3.2 μm by 0.5 to 0.8 μm and are surrounded by numerous flagella (peritrichous).
Virulence factors are molecules produced by bacteria, viruses, fungi, and protozoa that add to their effectiveness and enable them to achieve the following:
Food microbiology is the study of the microorganisms that inhibit, create, or contaminate food. This includes the study of microorganisms causing food spoilage; as well as, pathogens that may cause disease especially if food is improperly cooked or stored. Those used to produce fermented foods such as cheese, yogurt, bread, beer, and wine. Then those researchers with other useful roles such as producing probiotics.
Bacteria are a type of biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of the earth's crust. Bacteria also live in symbiotic and parasitic relationships with plants and animals. Most bacteria have not been characterised, and only about 27 percent of the bacterial phyla have species that can be grown in the laboratory . The study of bacteria is known as bacteriology, a branch of microbiology.
Genetically modified bacteria were the first organisms to be modified in the laboratory, due to their simple genetics. These organisms are now used for several purposes, and are particularly important in producing large amounts of pure human proteins for use in medicine.
Escherichia coli is a gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms (endotherms). Most E. coli strains are harmless, but pathogenic varieties cause serious food poisoning, septic shock, meningitis, or urinary tract infections in humans Unlike normal flora E. coli, the pathogenic varieties produce toxins and other virulence factors that enable them to reside in parts of the body normally not inhabited by E. coli and to damage host cells. These pathogenic traits are encoded by virulence genes carried only by the pathogens.
In biology, a pathogen in the oldest and broadest sense, is anything that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ.
The host-pathogen interaction is defined as how microbes or viruses sustain themselves within host organisms on a molecular, cellular, organismal or population level. This term is most commonly used to refer to disease-causing microorganisms although they may not cause illness in all hosts. Because of this, the definition has been expanded to how known pathogens survive within their host, whether they cause disease or not.
Enteroaggregative Escherichia coli are a pathotype of Escherichia coli is a cause of acute and chronic diarrhea in both the developed and developing world. They may also cause urinary tract infections. EAEC are defined by their "stacked-brick" pattern of adhesion to the human laryngeal epithelial cell line HEp-2. The pathogenesis of EAEC involves the aggregation of and adherence of the bacteria to the intestinal mucosa, where they elaborate enterotoxins and cytotoxins that damage host cells and induce inflammation that results in diarrhea.
Human interactions with microbes include both practical and symbolic uses of microbes, and negative interactions in the form of human, domestic animal, and crop diseases.