The branches of microbiology can be classified into pure and

applied science Applied science is the application of the scientific method and scientific knowledge to attain practical goals. It includes a broad range of disciplines, such as engineering and medicine. Applied science is often contrasted with basic science, ...

Microbiology Microbiology () is the branches of science, scientific study of microorganisms, those being of unicellular organism, unicellular (single-celled), multicellular organism, multicellular (consisting of complex cells), or non-cellular life, acellula ...

can be also classified based on

taxonomy image:Hierarchical clustering diagram.png, 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme o ...

, in the cases of

bacteriology Bacteriology is the branch and specialty of biology that studies the Morphology (biology), morphology, ecology, genetics and biochemistry of bacteria as well as many other aspects related to them. This subdivision of microbiology involves the iden ...

mycology Mycology is the branch of biology concerned with the study of fungus, fungi, including their Taxonomy (biology), taxonomy, genetics, biochemistry, biochemical properties, and ethnomycology, use by humans. Fungi can be a source of tinder, Edible ...

, protozoology, and phycology. There is considerable overlap between the specific branches of microbiology with each other and with other disciplines, and certain aspects of these branches can extend beyond the traditional scope of microbiology In general the field of microbiology can be divided in the more fundamental branch (pure microbiology) and the applied microbiology (

biotechnology Biotechnology is a multidisciplinary field that involves the integration of natural sciences and Engineering Science, engineering sciences in order to achieve the application of organisms and parts thereof for products and services. Specialists ...

). In the more fundamental field the organisms are studied as the subject itself on a deeper (theoretical) level. Applied microbiology refers to the fields where the micro-organisms are applied in certain processes such as brewing or fermentation. The organisms itself are often not studied as such, but applied to sustain certain processes.

Pure microbiology

Bacteriology Bacteriology is the branch and specialty of biology that studies the Morphology (biology), morphology, ecology, genetics and biochemistry of bacteria as well as many other aspects related to them. This subdivision of microbiology involves the iden ...

: the study of bacteria *

Mycology Mycology is the branch of biology concerned with the study of fungus, fungi, including their Taxonomy (biology), taxonomy, genetics, biochemistry, biochemical properties, and ethnomycology, use by humans. Fungi can be a source of tinder, Edible ...

: the study of fungi * Protozoology: the study of protozoa * Phycology/algology: the study of algae *

Parasitology Parasitology is the study of parasites, their host (biology), hosts, and the relationship between them. As a List of biology disciplines, biological discipline, the scope of parasitology is not determined by the organism or environment in questio ...

: the study of parasites *

Immunology Immunology is a branch of biology and medicine that covers the study of Immune system, immune systems in all Organism, organisms. Immunology charts, measures, and contextualizes the Physiology, physiological functioning of the immune system in ...

: the study of the immune system *

Virology Virology is the Scientific method, scientific study of biological viruses. It is a subfield of microbiology that focuses on their detection, structure, classification and evolution, their methods of infection and exploitation of host (biology), ...

: the study of viruses * Nematology: the study of nematodes * Microbial cytology: the study of microscopic and submicroscopic details of microorganisms * Microbial physiology: the study of how the microbial cell functions biochemically. Includes the study of microbial growth, microbial metabolism and microbial cell structure *

Microbial pathogenesis Microbial pathogenesis is a field of microbiology that started at least as early as 1988, with the identification of the triune Falkow's criteria, aka molecular Koch's postulates. In 1996, Fredricks and Relman proposed a seven-point list of "Molecul ...

: the study of

pathogens In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term ...

which happen to be microbes *

Microbial ecology Microbial ecology (or environmental microbiology) is a discipline where the interaction of Microorganism, microorganisms and their environment are studied. Microorganisms are known to have important and harmful ecological relationships within t ...

: the relationship between microorganisms and their environment * Microbial genetics: the study of how

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

s are organized and regulated in microbes in relation to their cellular functions Closely related to the field of

molecular biology Molecular biology is a branch of biology that seeks to understand the molecule, molecular basis of biological activity in and between Cell (biology), cells, including biomolecule, biomolecular synthesis, modification, mechanisms, and interactio ...

* Cellular microbiology: a discipline bridging microbiology and

cell biology Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living an ...

* Evolutionary microbiology: the study of the evolution of microbes. This field can be subdivided into: ** Microbial taxonomy: the naming and classification of microorganisms ***

Bacterial taxonomy Bacterial taxonomy is subfield of taxonomy devoted to the classification of bacteria specimens into taxonomic ranks. Archaeal taxonomy are governed by the same rules. In the scientific classification established by Carl Linnaeus, each species is ...

: the naming and classification of bacteria ** Microbial systematics: the study of the diversity and genetic relationship of microorganisms ** Microbial phylogenetics: the study of the manner in which various groups of

microorganism A microorganism, or microbe, is an organism of microscopic scale, microscopic size, which may exist in its unicellular organism, single-celled form or as a Colony (biology)#Microbial colonies, colony of cells. The possible existence of unseen ...

s are genetically relatedTalaro, Chess (2015) ''Foundations in Microbiology'' Page 21 ** Bacterial phylodynamics: the study of

immunology Immunology is a branch of biology and medicine that covers the study of Immune system, immune systems in all Organism, organisms. Immunology charts, measures, and contextualizes the Physiology, physiological functioning of the immune system in ...

epidemiology Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and Risk factor (epidemiology), determinants of health and disease conditions in a defined population, and application of this knowledge to prevent dise ...

, and

phylogenetics In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

of bacterial pathogens to better understand their

evolutionary Evolution is the change in the heritable characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certa ...

role **

Viral phylodynamics Viral phylodynamics is the study of how epidemiology, epidemiological, immune system, immunological, and evolutionary processes act and potentially interact to shape virus, viral Phylogenetic tree, phylogenies. Since the term was coined in 2004, re ...

: the study of how

epidemiological Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and Risk factor (epidemiology), determinants of health and disease conditions in a defined population, and application of this knowledge to prevent dise ...

immunological Immunology is a branch of biology and medicine that covers the study of immune systems in all organisms. Immunology charts, measures, and contextualizes the physiological functioning of the immune system in states of both health and disease ...

, and

evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

ary processes act and potentially interact to shape viral

phylogenies A phylogenetic tree or phylogeny is a graphical representation which shows the evolutionary history between a set of species or taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA. In o ...

* Generation microbiology: the study of those microorganisms that have the same characters as their parents * Systems microbiology: a discipline bridging

systems biology Systems biology is the computational modeling, computational and mathematical analysis and modeling of complex biological systems. It is a biology-based interdisciplinary field of study that focuses on complex interactions within biological system ...

and microbiology. *

Molecular microbiology Molecular biology is a branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. Though cells and other microsco ...

: the study of the molecular principles of the physiological processes in microorganisms

Other

* Astro microbiology: the study of microorganisms in outer space *

Biological agent Biological agents, also known as biological weapons or bioweapons, are pathogens used as weapons. In addition to these living or replicating pathogens, toxins and Toxin#Biotoxins, biotoxins are also included among the bio-agents. More than 1,2 ...

: the study of those microorganisms which are being used in weapon industries. * Nano microbiology: the study of those microscopic organisms on nano level. * Predictive microbiology: the quantification of relations between controlling factors in foods and responses of pathogenic and spoilage microorganisms using mathematical modelling *

Applied microbiology

* Medical microbiology: the study of the pathogenic microbes and the role of microbes in human illness. Includes the study of microbial

pathogenesis In pathology, pathogenesis is the process by which a disease or disorder develops. It can include factors which contribute not only to the onset of the disease or disorder, but also to its progression and maintenance. The word comes . Descript ...

and

and is related to the study of disease

pathology Pathology is the study of disease. The word ''pathology'' also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in the context of modern medical treatme ...

and

. This area of microbiology also covers the study of

human microbiota Human microbiota are microorganisms (bacteria, viruses, fungi and archaea) found in a specific environment. They can be found in the stomach, intestines, skin, genitals and other parts of the body. Various body parts have diverse microorganisms. S ...

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

, and the tumor microenvironment. * Pharmaceutical microbiology: the study of microorganisms that are related to the production of antibiotics, enzymes, vitamins, vaccines, and other pharmaceutical products and that cause pharmaceutical contamination and spoil. *

Industrial microbiology Industrial microbiology is a branch of biotechnology that applies microbial sciences to create industrial products in mass quantities, often using Microbial cell factory, microbial cell factories. There are multiple ways to manipulate a microorgani ...

: the exploitation of microbes for use in industrial processes. Examples include

industrial fermentation Industrial fermentation is the intentional use of fermentation in manufacturing processes. In addition to the mass production of fermented foods and drinks, industrial fermentation has widespread applications in chemical industry. Commodity ch ...

and

wastewater treatment Wastewater treatment is a process which removes and eliminates contaminants from wastewater. It thus converts it into an effluent that can be returned to the water cycle. Once back in the water cycle, the effluent creates an acceptable impact on ...

. Closely linked to the

industry. This field also includes

brewing Brewing is the production of beer by steeping a starch source (commonly cereal grains, the most popular of which is barley) in water and #Fermenting, fermenting the resulting sweet liquid with Yeast#Beer, yeast. It may be done in a brewery ...

, an important application of microbiology. * Microbial biotechnology: the manipulation of microorganisms at the genetic and molecular level to generate useful products. *

Food microbiology Food microbiology is the study of the microorganisms that inhabit, create, or contaminate food. This includes the study of microorganisms causing food spoilage; pathogens that may cause disease (especially if food is improperly cooked or stored); ...

: the study of microorganisms causing food spoilage and foodborne illness. Using microorganisms to produce foods, for example by fermentation. * Agricultural microbiology: the study of agriculturally relevant microorganisms. This field can be further classified into the following: ** Plant microbiology and

Plant pathology Plant pathology or phytopathology is the scientific study of plant diseases caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Plant pathology involves the study of pathogen identification, disease ...

: The study of the interactions between microorganisms and plants and plant pathogens. **

Soil microbiology Soil microbiology is the study of microorganisms in soil, their functions, and how they affect soil properties. It is believed that between two and four billion years ago, the first ancient bacteria and microorganisms came about on Earth's oceans. ...

: the study of those microorganisms that are found in soil. * Veterinary microbiology: the study of the role of microbes in

veterinary medicine Veterinary medicine is the branch of medicine that deals with the prevention, management, medical diagnosis, diagnosis, and treatment of disease, disorder, and injury in non-human animals. The scope of veterinary medicine is wide, covering all a ...

or animal

. *

Environmental microbiology ''Environmental Microbiology'' is a monthly peer-reviewed scientific journal focused on microbial interactions and microbial processes in the environment. It is published by Wiley-Blackwell. Until January 2024, it was an official journal of the S ...

: the study of the function and diversity of microbes in their natural environments. This involves the characterization of key bacterial habitats such as the

rhizosphere The rhizosphere is the narrow region of soil or Substrate (biology), substrate that is directly influenced by root secretions and associated soil microorganisms known as the root microbiome. Pore space in soil, Soil pores in the rhizosphere can ...

and phyllosphere,

soil Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...

and

groundwater Groundwater is the water present beneath Earth's surface in rock and Pore space in soil, soil pore spaces and in the fractures of stratum, rock formations. About 30 percent of all readily available fresh water in the world is groundwater. A unit ...

ecosystem An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...

s, open

oceans The ocean is the body of salt water that covers approximately 70.8% of Earth. The ocean is conventionally divided into large bodies of water, which are also referred to as ''oceans'' (the Pacific, Atlantic, Indian, Antarctic/Southern, and ...

or extreme environments (

extremophile An extremophile () is an organism that is able to live (or in some cases thrive) in extreme environments, i.e., environments with conditions approaching or stretching the limits of what known life can adapt to, such as extreme temperature, press ...

s). This field includes other branches of microbiology such as: **

** Microbially mediated

nutrient cycling A nutrient cycle (or ecological recycling) is the movement and exchange of inorganic and organic matter back into the production of matter. Energy flow is a unidirectional and noncyclic pathway, whereas the movement of mineral nutrients is cyc ...

Geomicrobiology Geomicrobiology is the scientific field at the intersection of geology and microbiology and is a major subfield of geobiology. It concerns the role of microbes on geological and geochemical processes and effects of minerals and metals to microbia ...

** Microbial diversity **

Bioremediation Bioremediation broadly refers to any process wherein a biological system (typically bacteria, microalgae, fungi in mycoremediation, and plants in phytoremediation), living or dead, is employed for removing environmental pollutants from air, wate ...

: use of micro-organisms to clean air, water and soils. * Water microbiology (or aquatic microbiology): The study of those microorganisms that are found in water. * Aeromicrobiology (or air microbiology): The study of airborne microorganisms. *

Biotechnology Biotechnology is a multidisciplinary field that involves the integration of natural sciences and Engineering Science, engineering sciences in order to achieve the application of organisms and parts thereof for products and services. Specialists ...

: related to recombinant DNA technology or genetic engineering.

References

{{reflist Microbiology