micrococcus luteus biochemical tests

The categorization of the Gram-positive cocci based on their possession of the enzyme catalase, a quality which can be easily assayed in the lab. They are likely involved in the biodegradation of many other environmental pollutants or detoxification. The GC content of the DNA ranges from about 65 to 75 mol%. The genus Micrococcus consists of Gram-positive spheres occurring in tetrads and in irregular clusters that are usually non-motile and non-spore-forming. They grow in circular, entire, convex, and creamy yellow-pigmented colonies with diameters of approximately 4 mm after 2-3 days at 37C. The oxygen class and the gram positiveness of the microbe also matches up with that of Micrococcus luteus. Retrieved 06:20, April 16, 2019, from https://en.wikipedia.org/w/index.php?title=Micrococcus_luteus&oldid=887698104, Wikipedia contributors. These organisms range in virulence potential from commensal organisms found on the skin and mucous membranes to pathogens associated with serious infections. The typical microscopic morphology of the Gram-positive cocci when using the Grams stain is represented in these three images. The name of the genus is also called " Germanized " is written as Micrococcus. . The staphylococci and micrococci are catalase producers while the streptococci, enterococci, and a variety of other Gram-positive cocci are catalase-negative. Catalase test was the first biochemical test to be done . "EPR and ENDOR detection of compound I from Micrococcus lysodeikticus catalase". document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Built with Enlightenment Theme and WordPress. (2) Micrococcus spp. Catalase, if present, will break down the hydrogen peroxide to water and oxygen. ? Those are extremely toxic because they are powerful oxidizing agents and destroy cellular constituents very rapidly. 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). Alpha-hemolytic colonies often assume a greenish hue. I used the PATRIC software to perform a metagenome binning and to assign a taxonomy to the bacteria. Simple biochemical tests like the one above have always been an important aid to identification of bacteria, because the different bacterial groups and species have characteristic metabolic activities. They are positive for catalase and oxidase ( modified). A very important test in the categorization of the staphylococci is the coagulase test. I suspect that the API 20E test strip results were negated by having used an inactive colony, as the fluid thyoglycate test failed as well. The streptococci and enterococci are categorized by expression of either beta, alpha, or gamma hemolysis on sBAP, depending on the genus/species. Micrococcus luteus is a constituent of the normal human buccal bacterial flora which forms yellowish colonies and appears as a gram-positive coccus typically arranged in tetrads. In order to determine physiological characteristics of the culture such as cell shape, arrangement, and whether it was gram positive or negative, which helps determine the cell wall type of the microbe, I performed a gram stain. It has been associated with causing a variety of illnesses including septic arthritis, meningitis, endocarditis, chronic cutaneous infections in HIV-positive patients, and catheter infections. Book a free counselling session. Micrococcus luteus biochemical test result. I kept the plate at room temperature for 7 days, and then selected a colony to purify using the pure culture streak plate method. So far there are two genome sequences that have been done. This would be read A/NC. 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. Intermediates or end products of these varied metabolic activities can be detected by performing biochemical assays on a bacterial culture. Staphylococcus aureus. Micrococcus species, members of the family Micrococcaceae, are usually regarded as contaminants from skin and mucous membranes. It is essential for differentiating catalase-positive Micrococcaceae from catalase-negative Streptococcaceae. They occur in pairs, tetrads or clusters but not in chains. In Wikipedia, The Free Encyclopedia. The catalase test did return positive by bubbling, indicating that it does have the ability to break down the radical hydrogen peroxide into diatomic oxygen and hydrogen. Basics of Differentiation of Gram Positive Cocci, Author: Karen Krisher In contrast to staphylococci, usually, penicillin is sensitive. When viewing the organism microscopically, the staining characteristics of the organism provide important information for identification. The staphylococci are characterized by the formation of clusters of many cocci. [3] Its genome was sequenced in 2010 and is one of the smallest genomes of free-living Actinomycetota sequenced to date, comprising a single circular chromosome of 2,501,097 bp.[4]. It is a gram positive, coccus shaped microbe, and contains catalase. Filter paper disks impregnated with tetramethyl-p-phenylenediamine dihydrochloride (oxidase reagent) in dimethyl sulfoxide (DMSO) are used. Perkins1, Sarah D., Jennie Mayfield2, and Victoria Fraser3 And. It did not reduce sulphur, digest gelatin, or reduce nitrate, among some of the more interesting tests, which all disagree with M. luteus. Micrococci can grow well in environments with little water or high salt concentrations, including sportswear that is made with synthetic fabrics. Micrococcus is a genus of bacteria that is present in the Micrococcaceae family. [7], In 2003, it was proposed that one strain of Micrococcus luteus, ATCC 9341, be reclassified as Kocuria rhizophila. This is termed alpha () hemolysis and results in a greenish color surrounding the colony. I then transferred the pure culture into a TSB slant to preserve it, keeping it at around 3 degrees Celsius in the lab refrigerator. When looking at the antibiotic test results, the isolate is resistant to none of the applied antibiotics, and is only lightly to intermediately resistant to oxacillin. The previous classification of these organisms was much simpler; however, with the use of more advanced genetic sequencing methods, these gram-positive cocci have expanded into 4 separate families and their associated genera. The identified reads only made up a total of twenty seven percent of the total reads, but the majority of those reads were for M. luteus. Characteristics. I also had to do the thyoglycate test 3 times to get a conclusive result, further making me skeptical of how active the culture was during the physical tests during week 6, which is where almost all of the inconsistencies arose. M. luteus tests positive for catalase, oxidase, utilization of D-glucose, sucrose and D-mannose, and has A2 type peptidoglycan that contains L-lysine as the diagnostic amino acid, MK-8 and MK-8 (H 2) are the major menaquinones (Stackebrandt et al. 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Many of the tests did line up with M. luteus though, such as the fluid thyoglycate test, which showed that it was an obligate aerobe. Though today the immuno-compromised patients take the risk of the infection that has grown. 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. November 27, 2021 at 9:14 AM Hi sir, why Macrococcus and Micrococcus will not ferment . Subscribe to our e-mail newsletter to receive updates. Micrococcus luteus ( M. luteus ), is a Gram-positive bacteria, 0.05 to 3.5 microns in diameter, that is most commonly found in mucous membranes such as the nasal cavities, the upper respiratory tract, and the lining of the mouth. Micrococcus spp. The catalase test facilitates the detection of the enzyme catalase in bacteria. These discrepancies could be due to human error, unpure culture, or an old agar plate. 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. The results of this analysis are shown in table 1. About half of the Micrococcus luteus gram stain was found to carry plasmids of about one to 100MDa in size. Bharath. The PYRA, PAL, LAP, RIB, ARA, MAN, and TRE tests came up as positive. They contain cytochromes and are resistant to lysostaphin. It is mostly Actinobacteria, but some Proteobacteria and Firmicules are in the sample as well. It is Gram-positive cocci in tetrads, catalase-positive, coagulase-negative, arranged in clusters that differ from Staphylococcus in attacking sugars oxidatively which may appear in irregular clusters, groups of four or eight. Biochemical Test Chart (You will not fill in every blank in this chart.) In a temporal study by Kloos and Musselwhite (1975), it was found that micrococci usually constituted from 1 to 20% of the total aerobic bacteria isolated from the skin of the head, legs, and arms, but less than 1% of those isolated from the high bacterial density areas of the nares and axillae. They are fairly small as well, usually about a millimeter in diameter and of a normal height. Micrococcus luteus uses the amino acids and does not grow in the butt of the slant. 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. 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 luteus can synthesize the iso-branched and anteiso-branched alkenes by the head-to-head condensation of fatty-acid thioesters. In future works with this microbe, I probably would want to purify the culture more and redo the tests. Most of the Micrococcus infections are discovered through the process of elimination along with the presence of the abundant Micrococcus tetrads in the lesions or cysts. The MacConkey agar showed very little growth, and did not have a change in color, indicating that the microbe was gram positive and not a fermenter. Micrococcus luteus are Gram-positive, to Gram-variable, motile -non motile, that are 0.5 to 3.5 micrometers in diameter and usually arranged in tetrads or irregular clusters. Micrococci are microbiologically characterized as gram-positive cocci, 0.5 to 3.5 m (micrometres; 1 m = 10-6 metre) in diameter. Another set of tests that I performed were physiological tests, including testing for oxygen class with fluid thyoglycate, checking for catalase using hydrogen peroxide, checking for cytochrome c oxidase using oxidase test strips, and using an API 20 E test strip to test for various different physiological traits such as Sulphur reduction, which had 20 different tests. Biochemical Tests in Microbiology Student Name Date 1 Lot Number(s) Record the lot numbers for each bacterial . Micrococcaceae. Micrococcus lutues are Gram positive cocci that are 0.5 to 3.5 m in diameter and arranged in tetrads or irregular clusters. M. luteus is part of the normal flora of the human skin.Transmission and DiseaseM. This bacterium can withstand massive doses of UV radiation and it also has the capability to degrade certain pollutants such as petrol. The family, Micrococcaceae, has been shrinking. Only the Micrococcus luteus species contained cytochrome c oxidase. Streptococcus pneumoniae and a group of streptococci referred to as viridans (green) streptococci are examples of bacteria producing alpha-hemolysis. 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. Micrococcus Luteus is a gram positive, non-motile, non-sporing cocci belonging to micrococcea family. 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. M. luteus causes odours in humans when breaking down the components of sweat. This is in agreement with a study by Mohana et al., (2013) who reported that the carotenoid pigments had antioxidant properties of Micrococcus luteus was reported at IC50 of 4.5mg/ml, also the . 1. Micrococcus luteusare Gram-positive cocci mostly arranged in tetrads and larger than Staphylococcus. This is likely either a cause of human error, unpure cultures, or not using agar plates that are fresh enough for the test. 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. The micrococci produce tetrads consisting of 4 cocci clustered together. Similar to the situation in the prosthetic valve endocarditis that is caused by more aggressive and highly resistant bacteria. Streptococcus spp. Staphylococci were distinguished by their ability to form acid from glucose anaerobically and sarcinas by the formation of cubical packets. Sarah D. Perkins., Government of Canada, Public Health Agency of Canada. The data on the GC content of the DNA, chemical cell wall analysis, and a comparative analysis of the 16S rRNA sequences. They are indole negative, oxidase-positive, catalase-positive, and citrate negative. This presentation will focus on the laboratory tests useful for the differentiation among the families as opposed to the more complicated differentiation and identification of the organisms within the different genera. The colony morphology of being yellow, shiny and smooth line up perfectly with M. luteus (Public Health England). Required fields are marked *. Klebsiella pneumoniae Micrococcus luteus Micrococcus roseus Proteus mirabilis Proteus vulgaris Pseudomonas aeruginosa Salmonella typhimurium Serratia marcescens Staphylococcus aureus Staphylococcus epidermidis Streptococcus . It is a gram positive, coccus shaped microbe, and contains catalase. It has survived for at least 34,000 to 170,000 years, as assessed by 16S rRNA analysis, and possibly much longer. If I were to continue researching this isolate, I would redo the API 20 E test strip with a fresh, active culture to ensure that it can reduce nitrate, and also the oxidase test to ensure that it does have cytochrome c oxidase present, which it should according to Public Health England. There have been several deaths in immuno-compromised children that are caused by leukemia from the pulmonary hemorrhages because of Micrococcus. I also hypothesize that it will be an aerobic organism, given that I found it in a well aerated environment and it has survived until I cultured it. It is an aerobic exopolysaccharide producing bacteria that may be found on the skin, mouth and sometimes in the throat of mammals 13,14. Micrococcus (pleural-micrococci) is free-living in the environment and also normal flora of the skin. Many members of the genus have been reclassified into other genera. I performed a Gram stain test to identify if the bacterium was gram negative or positive, as described in the Lab 4 handout. Your email address will not be published. On top of that, most of the bacterium that were stained were gram negative, which conflicts with this result. Your email address will not be published. What are the Diseases that are Caused By Micrococcus? When looking back at all the data, it is fairly likely that the isolate is Micrococcus luteus, especially when looking at the fluid thyoglycate test, the colony morphology, and the antibiotic susceptibility. I then repeated this three more times to further purify the isolate. The EMB agar showed no growth or change in color, also indicating the microbe was gram positive and a non-fermenter. Micrococcus spp. 2. // A number of sophisticated tools are now available for clinical diagnosis. Although it's tempting to write a summary of the entire study but it . Micrococci are usually not pathogenic. Micrococci have Gram-positive spherical cells ranging from about 0.5 to 3 micrometers in diameter and typically appear in tetrads. This bacterium can also be transmitted to others due to poor hand-washing practices. 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. Micrococcus is the Gram-positive cocci that are about 0.5 to 3.5 micrometres in diameter and usually, these are arranged in tetrads or in irregular clusters. Micrococcus luteus This Gram positive coccus is found in tetrads, irregular clusters, and cubical packets of eight. Mannitol salt agar (MSA) is a selective, differential, and indicator medium used to isolate and identify Staphylococcus aureus from the clinical specimen. Microbes are too small to be seen by the naked eye; they can survive in conditions that many would think are unlivable like the anaerobic environment in the rumen of cows, hot springs, and cold Antarctic waters (What are microbes, 2010). Micrococcus luteus is a Gram-positive to Gram-variable, nonmotile, tetrad-arranging, pigmented, saprotrophic coccus bacterium in the family Micrococcaceae. Micrococcus species are oxidase-positive, which can be used to distinguish them from other bacteria like most Staphylococcus species, which are generally oxidase-negative. [3] Staphylococcus spp. When looking at the genetic tests, most of the identified strains in the Korona test are Micrococcus luteus. download full PDF here, Some of the species of Micrococcus, such as M. luteus which is yellow in colour, and M. roseus which is red. 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%. Kaiju webserver metagenome binning analysis chart. The kaiju metagenome binning shows that the microbe sample is not completely pure (Figure 2). These residential skin organisms are also fairly ubiquitous in the environment. Date: FEB.11.2016 Some Micrococcus are pigmented bacteria; for example, M. luteus produces yellow colonies and M. roseus produces redish colonies. M. luteus has a G-C content of about 65-75 mol%. Care must be taken when using a sample of organism acquired from a sBAP since erythrocytes also produce catalase. 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. It shows that it is mostly Actinobacteria, with some firmicules ,and proteobacteria mixed in (Figure 2). Oral microbial flora of reptiles includes bacteria from Proteus, Porphyromonas, Micrococcus, Salmonella and Staphylococcus genera 5,8,15. In the presence of atmospheric oxygen, the oxidase enzyme reacts with the oxidase reagent and cytochrome C to form the coloured compound, indophenol indicated as blue or purplish-blue colouration on the disc after the introduction of the bacterial colony on the disc. 2. This can occur due to the presence of a reduced number of proteins that can bind to penicillin. M. luteus is an obligate aerobe (Medical Laboratories). This microbe forms large, round colonies. 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 . The large polysaccharide molecule starch contains two parts, amylose and amylopectin, these are rapidly hydrolyzed using a hydrolase called alpha-amylase to produce smaller molecules: dextrins, maltose, and glucose. Retrieved 22:17, April 16, 2019, from https://en.wikipedia.org/w/index.php?title=Staphylococcus_aureus&oldid=890960280, Your email address will not be published. Micrococcus luteus are Gram-positive cocci mostly arranged in tetrads and larger than Staphylococcus. Gram Stain:Gram-positive cocci, arranged in clusters that differ from Staphylococcus. The modified oxidase reagent is prepared as tetramethyl-p-phenylenediamine in certified grade dimethyl sulfoxide. Micrococcus luteus was one of the early examples of novel codon usage,[5][6] which led to the conclusion that the genetic code is not static, but evolves. Micrococcus luteus was formerly known as Micrococcus lysodeikticus. Reduction of O2 produces superoxide radicals and hydrogen peroxide, or the hydroxyl radical. The nasal cavity microbiota of healthy adults. The taxonomic assignment of this microbe was micrococcus luteus because it was the only bin that PATRIC gave. They are fairly ubiquitous in the environment, and are small (0.5 to 3.5 micrometers in diameter) and non-motile. M. luteus oxidizes carbohydrates to CO2 and water, and it does not produce acid from glucose as well as it does not make arginine dihydrolase or b-galactosidase. Staphylococcus aureus Staphylococcus spp. Several uncommon strains produce raised colonies with translucent, depressed centers. The coagulase test is performed by mixing a sample of organism with rabbit plasma. The metabolic pathways required for biomass production in silico were determined based on earlier models of actinobacteria. Annals of Allergy, Asthma and Immunology 122(1):17-24. Other articles where Micrococcus luteus is discussed: Micrococcus: found in milk, such as M. luteus, M. varians, and M. freudenreichii, are sometimes referred to as milk micrococci and can result in spoilage of milk products. Washington, DC 20001 The sample was then sequenced using the Illumina MiSeq technology in UAFs DNA Core Lab. They are found in soil, dust, water and air, and as part of the normal microbiota of skin. It is an opportunistic pathogen, only pathogenic enough to cause disease in weakened immune systems (Medical Laboratories). 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. 900 Seventh Street, NW Suite 400 Alcaligenes faecalis Bacillus megaterium . 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. I chose to sample bacteria from inside my roommates nose. Coagulase Results: Micrococcus A study with 188 micrococci, identified only to the genus level, demonstrated MICs at achievable concentrations for most -lactams, aminoglycosides, glycopeptides, clindamycin and the most active drug in vitro, rifampin. Micrococcus luteus is generally harmless but can become an opportunistic pathogen in immunocompromised people or those with indwelling catheters. M. luteus is found in the soil, dust, water, and human skin flora. The first control consisted of plates of agar-agar to test sterility. In the last control, agar-agar was inoculated with 1 mL of M. luteus washed live cells and incubated for 24 h at 37 C. The microbiome of the nose. This can occur due to the presence of a reduced number of, Most of the Micrococcus infections are discovered through the process of elimination along with the presence of the abundant Micrococcus tetrads in the lesions or cysts. Micrococcus luteus was found gram-positive cocci, non-spore forming, non-haemolytic, non-motile aerobic or facultative anaerobes, arranged in pairs, irregular clusters and tetrads. Oxidase (modified oxidase) test: Positive. The oxidase test results suggest that the microbe does not contain oxidase, despite what the metagenome binning test showed. They are also catalase-positive and often weakly oxidase-positive ( modified oxidase test positive). Colony pigmentation varies considerably but is usually different shades of yellow or cream-white. Bacillus megaterium fermented sugars but didn't grow in the anaerobic area of the butt. In the presence of atmospheric oxygen, the oxidase enzyme reacts with the oxidase reagent and cytochrome C to form the coloured compound, indophenol indicated as blue or purplish-blue colouration on the disc after the introduction of the bacterial colony on the disc. A summary table is included which lists the results of the identification criteria discussed in the tutorial. Growth or weak growth is observed at 45C, at pH 10, and in the presence of 10% sodium chloride (NaCl). They are generally strict aerobes and can generally reduce nitrate. Whereas the M. variant has a G-C content of about 66-72mol%. Culture Characteristics: Colonies are shades of yellow or red. M. luteus present on the human skin can transform compounds present in sweat into compounds with an unpleasant odour. Enterococcus faecalis. Habitat Micrococcus lives in a wide range of environments such as water, soil, and the dust whereas, Staphylococcus lives in the animal body. It is difficult to differentiate Kocuria from Micrococcus with conventional biochemical methods; therefore, these organisms are often reported together as Micrococcus/Kocuria species. The EMB plate is also selective for gram-negative bacteria which is probably why the bacteria didnt grow on it. This lines up with M. luteus resistances from the tests. It is Gram positive, Coagulase positive, catalase and oxidase positive non-motile bacteria. // There are 3 biovars of this organismand they possess quite diverse chemotaxonomic features with respect to their menaquinone systems, cell-wall compositions, and Fourier transform-infrared (FT-IR) spectroscopy patterns, as well as biochemical properties. To identify our isolate after obtaining the pure culture, we performed many different tests. J Gen Microbiol 30(1963)409-427 . My goal in this experiment was to isolate, characterize and identify a bacterial colony that arose from a sample taken from my roommates nose. 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. As its name suggests, mannitol salt agar (MSA) contains 1% mannitol (sugar), 7.5% salt, and agar as a solidifying agent. This is a test for aerobic (able to use oxygen) catalase-positive bacteria such as Staphylococcus and Micrococcus. For the detection of oxidase enzyme, filter paper circular disks impregnated with tetramethyl-p-phenylenediamine dihydrochloride in dimethyl sulfoxide are used. Micrococcus spp. 2019). This microbe is coccus shaped and forms in tetrads. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Built with Enlightenment Theme and WordPress. I repeated this process three more times to further purify the colony. Gram-positive organisms appear purple under the microscope as opposed to the other category of bacterial cell with its own unique cell wall, the Gram-negative rod or coccus, which stains red. Micrococcus luteus | Taxonomy - PubChem Apologies, we are having some trouble retrieving data from our servers. 1995; Wieser et al. I think that this culture was mostly Micrococcus luteus based on the Kaiju and metagenome binning results.