Microbial art, [1] agar art, [2] or germ art [3] is artwork created by culturing microorganisms in certain patterns. [4] The microbes used can be bacteria, yeast, fungi, or less commonly, protists. The microbes can be chosen for their natural colours or engineered to express fluorescent proteins and viewed under ultraviolet light to make them fluoresce in colour.
Agar plates are used as a canvas, while pigmented or fluorescent bacteria and yeasts represent paint. In order to preserve a piece of microbial art after a sufficient incubation, the microbe culture is sealed with epoxy. [2]
Microbe species can be artistically chosen for their natural colours to form a palette. Suitable species of bacteria (with their colours) include Bacillus subtilis (cream to brown), Chromobacterium violaceum (violet), Escherichia coli (colourless), Micrococcus luteus (yellow), Micrococcus roseus (pink), Proteus mirabilis , Pseudomonas aeruginosa (brown), Pseudomonas fluorescens (naturally blue-green fluorescent with pyoverdine), Serratia marcescens (pink or orange), Staphylococcus aureus (yellow), and Vibrio fischeri (bioluminescent). [5]
Yeast species – which are fungi – used in microbial art include Saccharomyces cerevisiae (yellow–white) Aspergillus flavus (yellow–green spores), Aspergillus ochraceus (yellow), Aureobasidium pullulans (black), Candida albicans (whitish buff), Candida sake , Candida sp. (whitish), Cladosporium herbarum (brown to black), Cladosporium resinae , Epicoccum nigrum (yellow, orange, red, brown, and black), Fusarium sp., Rhodotorula sp., and Scopulariopsis brevicaulis . [5] [lower-alpha 1]
Protist species used in microbial art include Euglena gracilis (photosynthetic, green) and Physarum polycephalum (yellow–green). [5]
A technique called "bacteriography" involves selectively killing certain areas of a bacterial culture with radiation in order to produce artistic patterns. After incubation, the culture is sealed with acrylic. [6]
The type of medium in the agar plates is also important. Chromagar Candida is a differential medium used to identify different Candida species. When grown on this medium, C. albicans is light green, C. tropicalis is steel blue with purple around the edges, and C. krusei is rose pink with white around the edges. [7] However, using a different medium, C. tropicalis has maroon colonies. [8] The color of the medium itself can also be changed using microbes. In TCBS agar, Bromthymol Blue and Thymol Blue turn yellow when pH decreases, such as when bacteria consume sucrose. In this way, the background color of the medium can be changed from dark green to light yellow. [9]
Alexander Fleming, who is commonly credited with the discovery of penicillin in 1928, was known for creating germ paintings. [3] Throughout his career, Fleming’s paintings became more colorful as he came to know more microbial species. He would incorporate them into his paintings of ballerinas, families, and other images. [10]
The biochemist Roger Tsien won the 2008 Nobel prize for chemistry for his contributions to knowledge of green fluorescent protein (GFP) that has been used to create art-like works. [11]
The American Society for Microbiology hosts an annual contest for microbial art: the Agar Art Contest. [2] The contest was organized after a picture from a Christmas tree, made by Rositsa Tashkova, went viral in 2014. [12] The 2015 edition covered 85 submissions, of which microbial art created by Mehmet Berkmen and Maria Peñil called Neurons won first place. [13] The artwork used yellow Nesterenkonia and orange Deinococcus and Sphingomonas . [14] [15]
In 2020, the ASM received over 200 submissions, and awarded first place to Joanne Dungo for her multi-plate creation titled "The Gardener." [16]
Agar, or agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae, primarily from "ogonori" (Gracilaria) and "tengusa" (Gelidiaceae). As found in nature, agar is a mixture of two components, the linear polysaccharide agarose and a heterogeneous mixture of smaller molecules called agaropectin. It forms the supporting structure in the cell walls of certain species of algae and is released on boiling. These algae are known as agarophytes, belonging to the Rhodophyta phylum. The processing of food-grade agar removes the agaropectin, and the commercial product is essentially pure agarose.
An agar plate is a Petri dish that contains a growth medium solidified with agar, used to culture microorganisms. Sometimes selective compounds are added to influence growth, such as antibiotics.
The American Society for Microbiology (ASM), originally the Society of American Bacteriologists, is a professional organization for scientists who study viruses, bacteria, fungi, algae, and protozoa as well as other aspects of microbiology. It was founded in 1899. The Society publishes a variety of scientific journals, textbooks, and other educational materials related to microbiology and infectious diseases. ASM organizes annual meetings, as well as workshops and professional development opportunities for its members.
A microbiological culture, or microbial culture, is a method of multiplying microbial organisms by letting them reproduce in predetermined culture medium under controlled laboratory conditions. Microbial cultures are foundational and basic diagnostic methods used as research tools in molecular biology.
A growth medium or culture medium is a solid, liquid, or semi-solid designed to support the growth of a population of microorganisms or cells via the process of cell proliferation or small plants like the moss Physcomitrella patens. Different types of media are used for growing different types of cells.
MacConkey agar is a selective and differential culture medium for bacteria. It is designed to selectively isolate Gram-negative and enteric bacteria and differentiate them based on lactose fermentation. Lactose fermenters turn red or pink on MacConkey agar, and nonfermenters do not change color. The media inhibits growth of Gram-positive organisms with crystal violet and bile salts, allowing for the selection and isolation of gram-negative bacteria. The media detects lactose fermentation by enteric bacteria with the pH indicator neutral red.
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 chemicals, such as acetic acid, citric acid, and ethanol are made by fermentation. Moreover, nearly all commercially produced industrial enzymes, such as lipase, invertase and rennet, are made by fermentation with genetically modified microbes. In some cases, production of biomass itself is the objective, as is the case for single-cell proteins, baker's yeast, and starter cultures for lactic acid bacteria used in cheesemaking.
Antibiotic sensitivity testing or antibiotic susceptibility testing is the measurement of the susceptibility of bacteria to antibiotics. It is used because bacteria may have resistance to some antibiotics. Sensitivity testing results can allow a clinician to change the choice of antibiotics from empiric therapy, which is when an antibiotic is selected based on clinical suspicion about the site of an infection and common causative bacteria, to directed therapy, in which the choice of antibiotic is based on knowledge of the organism and its sensitivities.
Simmons' citrate agar is used for differentiating gram-negative bacteria on the basis of citrate utilization, especially for distinguishing Gammaproteobacteria of the family Enterobacteriaceae or even between species of the same genus. For example, Salmonella enteritidis would yield a positive (blue) result on Simmons’ agar and thus be distinguished from other Salmonella species like Salmonella typhi, Salmonella pullorum, and Salmonella gallinarum, which would yield a negative (green) result.
In microbiology, streaking is a technique used to isolate a pure strain from a single species of microorganism, often bacteria. Samples can then be taken from the resulting colonies and a microbiological culture can be grown on a new plate so that the organism can be identified, studied, or tested.
Potato dextrose agar and potato dextrose broth are common microbiological growth media made from potato infusion and dextrose. Potato dextrose agar is the most widely used medium for growing fungi and bacteria.
Medical microbiology, the large subset of microbiology that is applied to medicine, is a branch of medical science concerned with the prevention, diagnosis and treatment of infectious diseases. In addition, this field of science studies various clinical applications of microbes for the improvement of health. There are four kinds of microorganisms that cause infectious disease: bacteria, fungi, parasites and viruses, and one type of infectious protein called prion.
Buffered charcoal yeast extract (BCYE) agar is a selective growth medium used to culture or grow certain types of bacteria, particularly the Gram-negative species Legionella pneumophila. It has also been used for the laboratory diagnosis of Acanthamoeba keratitis, Francisella and Nocardia spp. It contains L-cysteine amino acid and ferric pyrophosphate that assist in the growth of Legionnaire's species. The charcoal within the medium acts as a detoxicant because it decomposes hydrogen peroxide which is toxic to the legionellae. The yeast extract in BCYE is the rich source of nutrients (vitamins, nitrogen, and carbon) that the bacteria depends on for growth. BCYE also has ACES buffer which maintains an optimal pH level for the bacteria to grow which is around 6.9. BCYE may be supplemented with antibiotics to select for legionellae, especially if screening an environmental or non-potable water specimen.
Hektoen enteric agar is a selective and differential agar primarily used to recover Salmonella and Shigella from patient specimens. HEA contains indicators of lactose fermentation and hydrogen sulfide production; as well as inhibitors to prevent the growth of Gram-positive bacteria. It is named after the Hektoen Institute in Chicago, where researchers developed the agar.
Thiosulfate–citrate–bile salts–sucrose agar, or TCBS agar, is a type of selective agar culture plate that is used in microbiology laboratories to isolate Vibrio species. TCBS agar is highly selective for the isolation of V. cholerae and V. parahaemolyticus as well as other Vibrio species. Apart from TCBS agar, other rapid testing dipsticks like immunochromatographic dipstick is also used in endemic areas such as Asia, Africa and Latin America. Though, TCBS agar study is required for confirmation. This becomes immensely important in cases of gastroenteritis caused by campylobacter species, whose symptoms mimic that of cholera. Since no yellow bacterial growth is observed in case of campylobacter species on TCBS agar, chances of incorrect diagnosis can be rectified. TCBS agar contains high concentrations of sodium thiosulfate and sodium citrate to inhibit the growth of Enterobacteriaceae. Inhibition of gram-positive bacteria is achieved by the incorporation of ox gall, which is a naturally occurring substance containing a mixture of bile salts and sodium cholate, a pure bile salt. Sodium thiosulfate also serves as a sulfur source and its presence, in combination with ferric citrate, allows for the easy detection of hydrogen sulfide production. Saccharose (sucrose) is included as a fermentable carbohydrate for metabolism by Vibrio species. The alkaline pH of the medium enhances the recovery of V. cholerae and inhibits the growth of others. Thymol blue and bromothymol blue are included as indicators of pH changes.
Antarctica is one of the most physically and chemically extreme terrestrial environments to be inhabited by lifeforms. The largest plants are mosses, and the largest animals that do not leave the continent are a few species of insects.
In microbiology, the term isolation refers to the separation of a strain from a natural, mixed population of living microbes, as present in the environment, for example in water or soil, or from living beings with skin flora, oral flora or gut flora, in order to identify the microbe(s) of interest. Historically, the laboratory techniques of isolation first developed in the field of bacteriology and parasitology, before those in virology during the 20th century.
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.
Diagnostic microbiology is the study of microbial identification. Since the discovery of the germ theory of disease, scientists have been finding ways to harvest specific organisms. Using methods such as differential media or genome sequencing, physicians and scientists can observe novel functions in organisms for more effective and accurate diagnosis of organisms. Methods used in diagnostic microbiology are often used to take advantage of a particular difference in organisms and attain information about what species it can be identified as, which is often through a reference of previous studies. New studies provide information that others can reference so that scientists can attain a basic understanding of the organism they are examining.
Millicent "Mimi" Edna Goldschmidt is an American microbiologist. Goldschmidt is known for her pioneering work in the field of astrobiology in addition to her medical research and her contributions to rapid testing methods for detecting microbial contaminants. Goldschmidt is a professor emerita at the University of Texas.
