They are positive for catalase and oxidase ( modified). The first control consisted of plates of agar-agar to test sterility. Catalase, if present, will break down the hydrogen peroxide to water and oxygen. The catalase test also indicated that the microbe does not have catalase, despite the metagenomic binning test suggesting it. Micrococcus luteus is found in lots of places including skin, soil, dust, water, air, mouth, mucosae, oropharynx, and upper respiratory tract of humans (Wikipedia, Micrococcus luteus, 2019). The pathogen, Staphylococcus aureus, is notably coagulase-positive while most other members of the family are coagulase-negative. Cells are catalase positive, oxidase positive, and exhibit strictly aerobic metabolism. Included in the observation of the morphology of the colony is the effect that the bacterial growth has on the sheep erythrocytes in the agar medium. Wikipedia contributors. I hypothesized that it would be a bacteria commonly found in the nasal cavities and likely from the aforementioned phyla, so it would likely do best living in an aerobic, humid, and warm environment. In the case of a negative test, no colour change is observed. Retrieved 06:20, April 16, 2019, from https://en.wikipedia.org/w/index.php?title=Micrococcus_luteus&oldid=887698104, Wikipedia contributors. Micrococcus luteus. The identification of three different biovars within the species M. luteus has the advantage that the three groups can be differentiated without nomenclatural changes having to be introduced. Organisms commonly found on the body include Micrococcus, Staphylococcus, and Corynebacterium species (Dermnet New Zeland). The tetrads of the micrococci, the grape like clusters of the staphylococci, and the pairs and/or chains of the streptococci are shown. The colony took 16 days to be purified. [3] Most of the bacterium in the gram stains were gram negative, but a significant amount, about twenty percent, showed up as gram positive. 2- M. luteus 3- M.roseus Culture: - Strictly aerobic at 37C incubation (24 hr) - Grow on ordinary media Nutrient agar - Blood agar and on the Blood agar M. roseus (pink) M. luteus (white) M.varians (yellow) - On m annitol salt agar grow given r ise to rose or pink colonies except M. roseus. Streptococcus pneumoniae and a group of streptococci referred to as viridans (green) streptococci are examples of bacteria producing alpha-hemolysis. 900 Seventh Street, NW Suite 400 Bacteria Collection: Micrococcus luteus Additional Information. Growth or weak growth is observed at 45C, at pH 10, and in the presence of 10% sodium chloride (NaCl). Oxidase (modified oxidase) test: Positive. Maximum production of pigments was observed at 35C, pH 9 and at 4% (W/V) NaCl concentration. It had 27,372 contigs in assembly. Coagulase Results: The bacterium also colonizes the human mouth, mucosae, oropharynx and upper respiratory tract. The API 20 Strep test I used came up with no conclusive results. Is Micrococcus luteus indole positive? Methods: To start isolating the bacterium, I used a sterile swab wet with deionized water provided by the lab to pick up bacteria from the shower drain. What is the biochemical test for Micrococci roseus? This microbe forms large, round colonies. These include the slide or drop catalase test, the tube method, the semiquantitative catalase for the identification of Mycobacterium tuberculosis. With this almost universal range of survivable living conditions that microbes can live in (particularly bacteria), it would be reasonable to assume that there would be at least one variety living in such a nice, wet, and aerated place as my shower drain. The microscopic morphology of the organisms as visualized using the Grams stain can give initial clues as to the possible identification of the organism. Examples of the colony morphology associated with each family is represented on this slide. . Abstract Micrococcus luteus IFO 3333 cells, both treated with chemical reagents and non-treated, were observed with a scanning electron microscope (SEM). As the microbe is gram positive this means that it has a large peptidoglycan layer and lacks a lipopolysaccharide layer. When using a fluid thyoglycollate test it resulted in the isolate being a strict aerobe, with all of the bacterium being at the top of the medium where it is oxygenic. The EMB agar showed no growth or change in color, also indicating the microbe was gram positive and a non-fermenter. About half of the Micrococcus luteus gram stain was found to carry plasmids of about one to 100MDa in size. Optimum growth temperature is 25-37 C.
I grew my bacteria on an Eosin Methylene Blue (EMB) plate to see if it could ferment lactose and if it could grow with methylene blue which selects for gram negative bacteria. I then repeated this three more times to further purify the isolate. Obtain a glucose fermentation tube. Structure and PhysiologyThis bacteria is Gram-positive, spherical, and an obligate aerobe. 2002 can be divided into three biovars that are distinguished by several chemotaxonomic and biochemical traits: biovar I represented by the type strain of Micrococcus luteus; biovar II represented by strain D7 DSM 14234 CCM 4959; and biovar III . If the agar plate is held up to a light source, you can sometimes see through the agar, as is pictured on the left. (negative). Recent reports, however, confirm that micrococci may be associated with human infections, particularly in immunosuppressed patients. When looking back after culturing the isolate, these hypothesies were supported by several of the tests, and served as a good tool to steer me towards what the isolate may be. It is often larger thanStaphylococcus. The name of the genus is also called " Germanized " is written as Micrococcus. . Micrococcus Luteus Oxidase Test: The microdase test, also known as modified oxidase test is a rapid test to differentiate Staphylococcus from Micrococcus which are Gram-positive cocci possessing catalase enzymes. Micrococcus spp. In the final section of a study, it is essential to present important information, techniques, and variables. Isolates of the M. luteus have been found to overproduce the riboflavin, Micrococcus Luteus Gram Stain Characteristics, Micrococci have been isolated from the human skin, animal and dairy products, and in beer. Other Micrococcus isolates produce various useful products, such as long-chain aliphatic hydrocarbons for lubricating oils. AACC.org
The colony forms as a yellow, shiny round blob. Micrococcus (pleural-micrococci) is free-living in the environment and also normal flora of the skin. We were aiming to isolate a bacterium from this initial environmental sample by using repeated quadrant streaks to isolate single species colonies, therefore producing a pure culture that we could do a multitude of tests on which include Gram staining, genetic analysis and antibiotic testing along with many other tests. Coagulase production is used as a virulence factor by the organism. The modified oxidase reagent is prepared as tetramethyl-p-phenylenediamine in certified grade dimethyl sulfoxide. A positive test leads to the development of blue or purple-blue on the disc within two minutes. The modified oxidase reagent is prepared as tetramethyl-p-phenylenediamine in certified grade dimethyl sulfoxide. This is designated as beta ()-hemolysis. //
They are generally strict aerobes and these can generally reduce nitrate concentration. Biochemical Tests in Microbiology answer sheet - Biochemical Tests in Microbiology Pre-Laboratory - Studocu Biochemical Tests in Microbiology lab answer sheet biochemical tests in microbiology questions why do some microbes specialize to use different food source than Skip to document Ask an Expert Sign inRegister Sign inRegister Home The gram stain of this microbe showed that it is gram positive because it stained purple. All three types of hemolytic reactions are represented on this slide. The Culture Collections represent deposits of cultures from world-wide sources. 2. The Micrococcus genus is known to be found on dust particles, in water, on skin and skin glands in vertebrates, and some species can be found in milk. The EMB plate is also selective for gram-negative bacteria which is probably why the bacteria didnt grow on it. The Gram stain, while it was gram variable, does not ideally match with the genetic test that resulted in Micrococcus luteus, which can be gram variable but is usually gram positive (Bonjar). The M. luteus genome encodes about four sigma factors and fourteen response regulators, a finding indicative of the adaptation to a rather strict ecological niche. The species Micrococcus luteus (Schroeter 1872) Cohn 1872 (Approved Lists 1980) emend. Cultures:- Nutrient broth cultures of Micrococcus luteus and Proteus vulgaris (young cultures) Procedure: Wet Mount Preparation . Defining characteristics of Micrococcus are the ability to aerobically produce acid from glucose glycerol, aesculin hydrolysis, arginine dihydrolase, major pigment production, motility, and conversion of nitrate to nitrite. SUMMARY: 1250 Gram-positive and catalase-positive cocci were isolated from bacon, pig and human skin and dust, and their morphology, physiology and biochemical characters examined. They grow in circular, entire, convex, and creamy yellow-pigmented colonies with diameters of approximately 4 mm after 2-3 days at 37C. Ans: Micrococci, like many other representatives of the Actinobacteria, can be catabolically versatile, with the ability to utilize a wide range of unusual substrates, such as herbicides, pyridine, chlorinated biphenyls, and oil.
Most of the species produce carotenoid pigments. It is essential for differentiating catalase-positive Micrococcaceae from catalase-negative Streptococcaceae. The differentiation is based on the detection of the oxidase enzymes. M. luteus present on the human skin can transform compounds present in sweat into compounds with an unpleasant odour. Although of low virulence, the germs may become more pathogenic in patients with impaired resistance, colonizing the surface of heart valves. The microbiome of the nasal cavity can also change in response to environmental factors such as geographic location, and hygiene (Rawis et al. The agglutinability of the cells with antiserum containing anti-teichuronic acid antibody was examined. The colony morphology is the same as well, being round, shiny, and sort of flat (Medical Laboratories). Under the microscope they are round cells. A summary table is included which lists the results of the identification criteria discussed in the tutorial. The API test strips lack of results suggests that the I used the wrong test strip, I probably needed to use the Staph test instead of the Strep test, because the Strep test is for when Catalase is absent, but there could have been catalase present. M. luteus has the capability to show dormancy without the formation of spores. Label the slide with the name of the organism; Place 15 - 20 uL of the culture in the middle of the slide Based on the place of origin of the bacterium that I isolated, I hypothesize that it will either be one of the above bacterium or a similar water loving organism, likely one that also forms a biofilm.
Micrococcus luteus ( Scanning electron micrograph ) Micrococcus luteus is a Gram-positive bacterium of the genus Micrococcus. Micrococcus Catalase Test: The catalase test facilitates the detection of the enzyme catalase in bacteria. Though today the immuno-compromised patients take the risk of the infection that has grown. Micrococcus luteus was formerly known as Micrococcus lysodeikticus. Required fields are marked *. Micrococcus was first isolated by Alexander Fleming in 1929, as Micrococcus lysodeikticus before it was known as micrococcus luetus (Ganz et al, 2002) Micrococcus is generally thought of as harmless bacterium, but there have been rare cases of Micrococcus infections in people with compromised immune systems, as occurs with HIV patients. For example, M. luteus and M. lylae are 40-50% genetically different. M. luteus has one of the smallest genomes of actinobacteria with a circular chromosome of 2,501,097 base pairs and a GC content of 73%. Micrococcus luteus is a Gram-positive to Gram-variable, nonmotile, tetrad-arranging, pigmented, saprotrophic coccus bacterium in the family Micrococcaceae. Micrococci have Gram-positive spherical cells ranging from about 0.5 to 3 micrometers in diameter and typically appear in tetrads. View Online Copy of Unknown ID Chart.xlsx from BIOL 250L at University of South Carolina. Biochemical 1- Catalase (+ve) 2- Coagulase (-ve) The sample was then sequenced using the Illumina MiSeq technology in UAFs DNA Core Lab. //
This simple-to-perform test categorizes the Gram-positive cocci as either catalase producers (+) or non-producers (-). 2002). "EPR and ENDOR detection of compound I from Micrococcus lysodeikticus catalase". Figure 1. Unlike other actinobacteria, M. luteus expresses only one resuscitation-promoting factor that is required for the emergence from dormancy and has few other dormancy-related proteins. Colonies typically have a lemon-yellow pigment. Wikipedia also says that Micrococcus luteus is an obligate aerobe, backing up what my results show (2019). It has survived for at least 34,000 to 170,000 years, as assessed by 16S rRNA analysis, and possibly much longer. The skin infections or chronic cutaneous infections that are caused can result in pruritic eruptions of the skin in some of the areas as well as scattered papule lesions with or without central ulcerations. Micrococcus luteus uses the amino acids and does not grow in the butt of the slant. Once a presumptive identification has been made based on colony and microscopic morphology and the catalase reaction, additional tests can be performed to establish the genus and species of the organism. The API 20 E test strip results revealed nothing about what the isolate uses as an electron acceptor because every result was negative, and that it likely only uses glucose as an energy and carbon source and oxygen as its electron acceptor. In this presentation, we will discuss the fundamentals of the primary identification of those microorganisms that are members of four main families of Gram-positive cocci, the Micrococcaceae, the Staphylococcaceae, the Streptococcaceae, and the Enterococcaceae. Genus: Micrococcus. The sequencing of Micrococcus luteus was supported because of its major potential role in the case of bioremediation and its importance in the field of biotechnology. Growth can produce colonies of a certain size and consistency, as well as pigmentation. luteus is capable of surviving in environments I performed many tests to find out the colony morphology and physiology. So far there are two genome sequences that have been done. Notice that beta-hemolysis results in a total lysis or clearing of the agar in the area of colony growth. They usually can occur in the irregular clusters, tetrads, and in pairs, where the individual cells are about one to 1.8 mm in diameter and these are usually non-motile and non-spore-forming in nature. Shape (Cocci/Diplococci/Rods) Cocci. I also grew it in a MacConkey (MAC) plate to see if it could ferment lactose and if it could grow with both crystal violet and bile salts to further confirm if it was gram negative or positive. The oxidase test tests to see if the microbe contains cytochrome c oxidase. The genera Staphylococcus, Micrococcus and Sarcina were recognized. They can be found in boiling hot springs; they can be found in frigid waters in the artic. Habitat Micrococcus lives in a wide range of environments such as water, soil, and the dust whereas, Staphylococcus lives in the animal body. The genus Micrococcus consists of Gram-positive spheres occurring in tetrads and in irregular clusters that are usually non-motile and non-spore-forming. On top of that, most of the bacterium that were stained were gram negative, which conflicts with this result. A very important test in the categorization of the staphylococci is the coagulase test. Catalase is an enzyme produced by the organism to neutralize the toxic effects of hydrogen peroxide in the environment of the cell. Micrococcus luteus Grown on BrainHeart Infusion Agar, Klebsiella characteristics on MacConkey Agar, Clinical Case Leukocyte Vacoulation Bacterial Infection, Segmented neutrophilic granulocyte during degradation, DIC (Disseminated intravascular coagulation), Creatinine Phosphate Kinase (CPK) and CK-MB Overview. There have been several deaths in immuno-compromised children that are caused by leukemia from the pulmonary hemorrhages because of Micrococcus. CCTC (English)
They are catalase positive and often oxidase positive although this reaction may be weak (see Table 23.3 ). Due to the thick structure of the bacterial cell wall, Gram-positive cocci retain the primary Grams stain, Crystal Violet. [1] It is urease and catalase positive. See answer (1) best answer. To sample, I used sterile cotton swabs and streaked them on TSA plates. Microbiome 2(27). Micrococcus luteus characteristics possess unusual abilities to tolerate and to use very toxic organic molecules as carbon sources and it combines these activities with tolerance to metals. It did not reduce sulphur, digest gelatin, or reduce nitrate, among some of the more interesting tests, which all disagree with M. luteus. If the infection leads to severe hemodynamic alterations, thus the valve replacement may become necessary. These residential skin organisms are also fairly ubiquitous in the environment. Three bacteria, E.coli, Staphylococcus epidermis, and Micrococcus luteus, have been grown on TSI or Triple sugar iron agar medium, which is a . Some of the Micrococcus are pigmented bacteria, for example, M. roseus produces reddish colonies and M. luteus produces yellow colonies. Micrococcus luteus in tetrads arrangement. 2019). Micrococcus species, members of the family Micrococcaceae, are usually regarded as contaminants from skin and mucous membranes. The optimum growth temperature is 25-37C. The metabolic pathways required for biomass production in silico were determined based on earlier models of actinobacteria. Whereas the M. variant has a G-C content of about 66-72mol%.
Exposure to these wavelengths of ultraviolet light has been correlated with an increased incidence of skin cancer, and scientists believe this pigment can be used to make a sunscreen that can protect against ultraviolet light.[9]. It is difficult to differentiate Kocuria from Micrococcus with conventional biochemical methods; therefore, these organisms are often reported together as Micrococcus/Kocuria species. The Kocuria rhizophila strain ATCC 9341 has been used in quality control for sterility testing, as a test for the effectiveness of antibiotics and fungicides, and for doxycycline, tetracycline, and chloramphenicol susceptibility testing since 1966 under the designation Micrococcus luteus [4]. Micrococcus luteus is coagulase negative, bacitracin susceptible, and forms bright yellow colonies on nutrient agar. Micrococcus luteus (left) Alcaligenes faecalis (middle) Reduction of nitrate to nitrite to be used as a final electron acceptor/Nitrate reductase. Enterococcus spp. 2023 Universe84a.com | All Rights Reserved, Blog: Microbiology and infectious disease, Anti-Mullerian Hormone (AMH) Test: Introduction, Result, Unit, Normal Range, Test Method, Clinical Significance, and Keynotes, Anti -TPO Antibody: Introduction, Test Result, Unit, Normal Range, Assaying Method, and Keynotes, HPV Genes detection using Real-Time PCR: Introduction, Principle, Test Requirements, Procedure, Result Interpretation and Keynotes, Microbiology Reporting Techniques: Introduction, List of Templates, and Keynotes, Acetamide Utilization Test: Introduction, Composition, Principle, Test Requirements, Procedure, Result-Interpretation, Limitations, and Keynotes, https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/887570/UK_SMI_ID_07i4.pdf, https://en.wikipedia.org/wiki/Micrococcus_luteus, https://europepmc.org/article/med/14576986, https://www.ajicjournal.org/article/S0196-6553(13)01146-2/fulltext. In contrast to staphylococci, usually, penicillin is sensitive. Take a clean, scratch free glass slide. They are positive for catalase and oxidase ( modified). The mammalian skin that has M. luteus strain is also highly sensitive to the beta-lactam antibiotics. They are considered as normal comensal of human skin and upper respiratory tract. The laboratory assay is performed by mixing a sample of the bacterial colony with a drop(s) of hydrogen peroxide placed on a microscope slide. Micrococcus luteus is coagulase negative, bacitracin susceptible, and forms bright yellow colonies on nutrient agar. M. luteus played an important part in Flemings discovery of Lysozyme which is the bodys natural antibiotic. M. luteus is part of the normal flora of the human skin.Transmission and DiseaseM. An interesting remaining family member, Microoccus antarcticus, was isolated from Antarctica, and is capable of growing at 4C. Finally I used different antibiotic disks to check for its resistance to antibiotics, using Gentamicin, Cefoperazone, Vancomycin, Tobramycin, Amikacin, Trimethoprim, Oxacillin, and Cefazdin. Your email address will not be published. Micrococcus luteus are Gram-positive cocci mostly arranged in tetrads and larger than Staphylococcus. This is a test for aerobic (able to use oxygen) catalase-positive bacteria such as Staphylococcus and Micrococcus. The M. luteus genome encodes about four sigma factors and fourteen response regulators, a finding indicative of the adaptation to a rather strict ecological niche. There are around nine species that are recognized in the genus. Perkins1, Sarah D., Jennie Mayfield2, and Victoria Fraser3 And. Colony pigmentation varies considerably but is usually different shades of yellow or cream-white. M. luteus has one of the smallest genomes of all the bacteria. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Built with Enlightenment Theme and WordPress. For the micrococci, susceptibility to the antimicrobial agents, bacitracin and furazolidone, as well as the modified oxidase test can be performed to distinguish this group from the staphylococci. M. luteus is found in the soil, dust, water, and human skin flora. For the micrococci, susceptibility to the antimicrobial agents, bacitracin and furazolidone, as well as the modified oxidase test can be performed to distinguish this group from the staphylococci.
M. lylae can be distinguished from the closely related species Micrococcus luteus by lysozyme susceptibility, genetic composition, and the type of cell-wall peptidoglycan. It is mostly Actinobacteria, but some Proteobacteria and Firmicules are in the sample as well. Biochemical Test Chart (You will not fill in every blank in this chart.) Micrococcus, genus of spherical bacteria in the family Micrococcaceae that is widely disseminated in nature. Micrococcus species are strictly aerobic Gram-positive cocci arranged in tetrads or irregular clusters, and cells range from 0.5 to 3 m in diameter. Micrococcus Luteus is a gram positive, non-motile, non-sporing cocci belonging to micrococcea family. [7], In 2003, it was proposed that one strain of Micrococcus luteus, ATCC 9341, be reclassified as Kocuria rhizophila. In the case of a negative test, no colour change is observed. The micrococci produce tetrads consisting of 4 cocci clustered together. Several uncommon strains produce raised colonies with translucent, depressed centers. Enterococcus faecalis. They grow on simple media and their colonies are usually pigmented. Hybridization studies show that there is no close genetic relationship between the species of Micrococcus bacteria. As mentioned, the type of hemolytic reaction produced on sBAP is a major clue toward the identification of the genus.