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Micrococcus luteus has been shown to survive in oligotrophic environments for extended periods of time. 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. Krona chart of microbe shows bacterial classes thought to be present in the sample. 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. Micrococci have Gram-positive types of spherical cells that are ranging from about 0.5 to three micrometres in diameter and typically they appear in tetrads. The data on the GC content of the DNA, chemical cell wall analysis, and a comparative analysis of the 16S rRNA sequences. It has been isolated from human skin. This lines up with M. luteus resistances from the tests. Wikipedia contributors. The oxygen class and the gram positiveness of the microbe also matches up with that of Micrococcus luteus. 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. 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. Luteus is an obligate aerobe (medical. 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. The partial decomposition of the hemoglobin of the erythrocytes by a weaker hemolysin. 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). This fits well with where I sampled my bacterium from, as a shower drain is a place where both dust and water would accumulate, along with residues of skin glands from showering. What are the Diseases that are Caused By Micrococcus? Many members of the genus have been reclassified into other genera. Staphylococcus epidermidis contains cytochrome c which leads to turned purple after oxidation. As mentioned, the type of hemolytic reaction produced on sBAP is a major clue toward the identification of the genus. For example, M. luteus and M. lylae are 40-50% genetically different. They are considered as normal comensal of human skin and upper respiratory tract. 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. The modified oxidase reagent is prepared as tetramethyl-p-phenylenediamine in certified grade dimethyl sulfoxide. Microbiome 2(27). This simple-to-perform test categorizes the Gram-positive cocci as either catalase producers (+) or non-producers (-). Micrococcus as the cause of infections is easy to overlook because the infections that are caused by this bacterium are rare as well as the bacterium is a natural part of the skin's bacterial flora. It grew in circular, entire, convex and creamy yellow pigmented colonies heaving 0.5-2.5 diameter. They grow in circular, entire, convex, and creamy yellow-pigmented colonies with diameters of approximately 4 mm after 2-3 days at 37C. The reactions of the four isolates indicated that they belonged to the species M. Zuteus (Kocur & Martinec, 1972). Cells are catalase positive, oxidase positive, and exhibit strictly aerobic metabolism. Micrococcus Luteus is a gram positive, non-motile, non-sporing cocci belonging to micrococcea family. Micrococcus spp. The negative oxidase result conflicts with M. luteus (Public Health England). 2019). The kaiju metagenome binning shows that the microbe sample is not completely pure (Figure 2). The catalase and the oxidase tests came up negative, because the catalase test did not form bubbles, and the oxidase test did not see a color change. Once the culture was deemed pure enough, I inoculated a slant tube. Because of their diversity, there are a variety of biochemical tests that are used by laboratories to identify the Gram-positive cocci. 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. When performing tests for physiological traits, the results were limited. // From: Infectious Diseases (Third Edition), 2010 View all Topics About this page These results might not be trustworthy. Reduction of O2 produces superoxide radicals and hydrogen peroxide, or the hydroxyl radical. Kaiju webserver metagenome binning analysis chart. A very important test in the categorization of the staphylococci is the coagulase test. Required fields are marked *. Some streptococci also possess unique cell wall carbohydrate antigens that can be identified by reactivity with specific indicator antibodies in an agglutination assay (Lancefield typing). It has been isolated from human skin. Micrococci are microbiologically characterized as gram-positive cocci, 0.5 to 3.5 m (micrometres; 1 m = 10-6 metre) in diameter. They are usually normal flora but can be opportunistic pathogens in certain immunocompromised patients. The Gentamicin, Cefoperazone, Vancomycin, Tobramycin, Amikacin, Trimethoprim, and Cefazdin antibiotics showed obvious susceptibility, with most of them having enormous rings of 50 to 52 millimeters while the threshold for resistance is only 15 millimeters. Micrococcus spp. The differentiation is based on the detection of the oxidase enzymes. . All of these are described in the lab 6 handout and were kept in the incubator at 38 degrees Celsius. When looking at the genetic tests, most of the identified strains in the Korona test are Micrococcus luteus. They are positive for catalase and oxidase ( modified). They are found in many other places in the environment, including dust, water, and soil. 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. They have a respiratory metabolism, often producing little or no acid from carbohydrates, and are usually halotolerant, growing in 5% NaCl. The gram stain of this microbe showed that it is gram positive because it stained purple. 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. A positive test leads to the development of blue or purple-blue on the disc within two minutes. Though today the immuno-compromised patients take the risk of the infection that has grown. See answer (1) best answer. The colonies are a pale, translucent yellow, and are shiny when looked at in the light. Micrococci may be distinguished from staphylococci by a modified oxidase test as shown below-. Micrococcus lylaeare Gram-positive cocci mostly arranged in tetrads. 2014). Micrococcus luteus. I chose to sample bacteria from inside my roommates nose. M. luteus is the majority of reads on the species level. This bacterium can withstand massive doses of UV radiation and it also has the capability to degrade certain pollutants such as petrol. They grow in circular, entire, convex, and creamy yellow-pigmented colonies with diameters of approximately 4 mm after 2-3 days at 37C. [3] Examples of the colony morphology associated with each family is represented on this slide. They are seldom motile and are non-sporing. 1. Alcaligenes faecalis Bacillus megaterium . For example, Micrococcus varians is now known as Kocuria varians. The tests that did not agree were most likely from not having an active colony used in the experiment, such as the oxidase test being negative or the API 20 E test strip showing that the isolate did not reduce nitrate, which it does, referencing Medical Laboratories. Micrococcus luteuswere discovered by Sir Alexander Fleming before he discovered penicillin in 1928. Download Scientific Diagram from www.researchgate.net. Gram Staining. M. luteus has the capability to show dormancy without the formation of spores. Oral microbial flora of reptiles includes bacteria from Proteus, Porphyromonas, Micrococcus, Salmonella and Staphylococcus genera 5,8,15. Gamma or no hemolysis results in no characteristic display in the vicinity of the colony. While every effort is made to ensure details distributed by Culture Collections are accurate, Culture Collections cannot be held responsible for any inaccuracies in the data supplied. I grew my isolated in Tryptic Soy Broth (TSB) for a week to prepare for DNA extraction. Recently, as an opportunistic pathogen, this organism was recognized and it has been implicated in recurrent bacteremia, septic arthritis, septic shock, endocarditis, intracranial suppuration, meningitis, and cavitating pneumonia in immunosuppressed patients. Coagulase, which is an enzyme involved in the conversion of serum fibrinogen to fibrin, causes the clotting of plasma. The oxidase test was negative, as the strip did not change color at all, where it would have turned purple if it was positive. Like MSA, this medium also contains the pH indicator, phenol red. Intro: Microbes are everywhere, even in the most extreme environments and conditions. It can be easily be mistaken for staphylococci, as they are very similar morphologically and physiologically (Wikipedia, Staphlyococcus Aureus). Annals of Allergy, Asthma and Immunology 122(1):17-24. 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. 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]. Micrococcus has a substantial cell wall in which it may comprise as much as 50% of the cell mass. 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. Micrococcus is a genus of bacteria that is present in the Micrococcaceae family. Table 1: Graph from Korona showing the percent reads of each organism, and to which taxonomic level. M. luteus is considered an opportunistic pathogen that can be responsible for some of the nosocomial infections. These can indicate that the genus of the Micrococcus is more closely related to the genus Arthrobacter than it is to other coccoid genera such as Staphylococcus and Planococcus. Micrococcus., h. Shahidi Bonjar. It did not reduce sulphur, digest gelatin, or reduce nitrate, among some of the more interesting tests, which all disagree with M. luteus. This kit utilizes enzymatic reactions to release bacterial DNA from the cell. (2019, April 4). I used an oxidase test strip and water to determine if cytochrome C oxidase was present, and performed a catalase test to determine if catalase was present. Complete lysis of the erythrocytes in the vicinity of the growing colony. They can even survive in conditions that have very little of even no oxygen, using glycolysis and alternative electron acceptors to create ATP. 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(2) Micrococcus spp. If the agar plate is held up to a light source, you can sometimes see through the agar, as is pictured on the left. The taxonomic assignment of this microbe was micrococcus luteus because it was the only bin that PATRIC gave. M. luteus played an important part in Flemings discovery of Lysozyme which is the bodys natural antibiotic. Colony morphology, the elucidation of the characteristics of the growth of the bacterium on agar medium, in most cases trypticase soy agar containing 5% sheep blood (sBAP). Of those only Vancomycin was closer than 50 millimeters, being 38 millimeters. Micrococcus luteus was formerly known as Micrococcus lysodeikticus. It is mostly Actinobacteria, but some Proteobacteria and Firmicules are in the sample as well. The family, Micrococcaceae, has been shrinking. Some of the species of Micrococcus, such as M. luteus which is yellow in colour, and M. roseus which is red. are gram-positive, oxidase-positive, and strictly they are aerobic cocci that are belonging to the family Micrococcaceae. Thus, when dealing with Micrococcus infections, it usually takes several cultures that are being grown and examined before one realizes that Micrococcus is indeed the culprit. My goal in this experiment was to isolate, characterize and identify a bacterial colony that arose from a sample taken from my roommates nose. Subscribe to our e-mail newsletter to receive updates. Micrococcus species by the Taxo A Bacitracin disk test can also be differentiated from staphylococcus species. 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 biochemical test result. In the 1920s, Alexander Fleming described lysozyme as a bactericidal factor of human and other animal tissues and secretions.1 He also discovered and named a yellow bacterium, Micrococcus lysodeikticus (now M luteus), that was highly susceptible to lysozyme-mediated killing.After exploring the susceptibility of other bacteria to lysozyme, Fleming proposed that M luteus and certain other . The organism itself is susceptible to almost all drugs, with a few strains being resistant to nitrofurantoin, macrolides and lincomycin (Public Health Canada). Washington, DC 20001 Catalase is an enzyme produced by the organism to neutralize the toxic effects of hydrogen peroxide in the environment of the cell. Micrococcus luteus | Taxonomy - PubChem Apologies, we are having some trouble retrieving data from our servers. Micrococcus, genus of spherical bacteria in the family Micrococcaceae that is widely disseminated in nature. Take a clean, scratch free glass slide. Micrococcus luteus ( Scanning electron micrograph ) Micrococcus luteus is a Gram-positive bacterium of the genus Micrococcus. 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. I then transferred the pure culture into a TSB slant to preserve it, keeping it at around 3 degrees Celsius in the lab refrigerator. Similar to the situation in the prosthetic valve endocarditis that is caused by more aggressive and highly resistant bacteria. These residential skin organisms are also fairly ubiquitous in the environment. (negative). 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. 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). Micrococcus species, members of the family Micrococcaceae, are usually regarded as contaminants from skin and mucous membranes. This would be read K/NC. Each family of Gram-positive cocci has its own unique configuration. Micrococci have Gram-positive spherical cells ranging from about 0.5 to 3 micrometers in diameter and typically appear in tetrads. "EPR and ENDOR detection of compound I from Micrococcus lysodeikticus catalase". Each genus lends itself to a separate tutorial. M. lylae can be distinguished from the closely related species Micrococcus luteus by lysozyme susceptibility, genetic composition, and the type of cell-wall peptidoglycan. This test had VP, HIP, ESC, PYRA, aGAL, bGUR, bGAL, PAL, LAP, ADH, RIB, ARA, MAN, SOR, LAC, TRE, INU, RAF, AMD, and GLYG tests. 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. 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. 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). Micrococcus lutues are Gram positive cocci that are 0.5 to 3.5 m in diameter and arranged in tetrads or irregular clusters. 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. They are generally strict aerobes and these can generally reduce nitrate concentration. 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. They are indole negative, oxidase-positive, catalase-positive, and citrate negative. Gram Stain:Gram-positive cocci, arranged in clusters that differ from Staphylococcus. 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. Environmental Testing. The microbiome of the nose. So far there are two genome sequences that have been done. The oxygen class of the microbe, obligate aerobe, matches up with the predictions I had made about it because the bacteria was originally sourced in a nostril. Wikipedia also says that Micrococcus luteus is an obligate aerobe, backing up what my results show (2019). 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. Hemolysis is the lysis of the sheep erythrocytes within the agar by bacterial toxins (hemolysins) that are produced by the different genera of Gram-positive cocci. The name of the genus is also called " Germanized " is written as Micrococcus. Hybridization studies indicate that species within the genus Micrococcus are not closely related, showing as little as 50% sequence similarity. Due to the thick structure of the bacterial cell wall, Gram-positive cocci retain the primary Grams stain, Crystal Violet. Hybridization studies show that there is no close genetic relationship between the species of Micrococcus bacteria. Most of the species produce carotenoid pigments. The pathogen, Staphylococcus aureus, is notably coagulase-positive while most other members of the family are coagulase-negative. The API 20 Strep test I used came up with no conclusive results. On top of that, most of the bacterium that were stained were gram negative, which conflicts with this result. Most of the bacterium in the gram stains were gram negative, but a significant amount, about twenty percent, showed up as gram positive. These families of bacteria produce colonies which are variable both in size, consistency, and the type of hemolysis produced on sBAP. The mammalian skin that has M. luteus strain is also highly sensitive to the beta-lactam antibiotics. So far there are two genome sequences that have been done. Micrococcus is a spherical bacterium found on dead or decaying organic matter while Staphylococcus is a gram-positive bacterial genus that produces a bunch of grape-like bacterial clusters. In Wikipedia, The Free Encyclopedia. Bassis CM, AL Tang, VB Young, and MA Pynnonen (2014). After you have cultivated your organism on agar media, the next step is the microscopic examination. Filter paper disks impregnated with tetramethyl-p-phenylenediamine dihydrochloride (oxidase reagent) in dimethyl sulfoxide (DMSO) are used. Figure 1. They are normal inhabitants of the human body and may even be essential in keeping the balance among the various . They grow on simple media and their colonies are usually pigmented. After it was sequenced using an Illumina MiSeq at the UAF Core lab, I used the online program Base Space to analyze the reads that I got from sequencing. Alpha-hemolytic colonies often assume a greenish hue. 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 are Gram-positive cocci mostly arranged in tetrads and larger than Staphylococcus. Staphylococcus saprophyticus is a Gram-positive, coagulase-negative coccus that is an important part of the group of microorganisms causing urinary tract infections (UTIs), particularly in young sexually active females. A positive test leads to the development of blue or purple-blue on the disc within two minutes. Although the Micrococcus rarely causes infections or problems in the body, with the compromised immune systems, it has been known to get certain skin infections that are caused by Micrococcus luteus. Micrococcus luteus uses the amino acids and does not grow in the butt of the slant. Micrococcus Public Health Agency of Canada., Public Health England. Organisms commonly found on the body include Micrococcus, Staphylococcus, and Corynebacterium species (Dermnet New Zeland). Micrococci can grow well in environments with little water or high salt concentrations, including sportswear that is made with synthetic fabrics. About half of the Micrococcus luteus gram stain was found to carry plasmids of about one to 100MDa in size. I used an API Strep test to determine more of the sugars the bacteria could ferment. However, the most promising antibiotic regimen that is proposed for the treatment of the Micrococcus luteus seems to be a combination of amikacin, vancomycin, and rifampicin. Staphylococci are either producers of the enzyme coagulase or non-producers. The EMB plate is also selective for gram-negative bacteria which is probably why the bacteria didnt grow on it. Micrococcus luteus is a Gram-positive to Gram-variable, nonmotile, tetrad-arranging, pigmented, saprotrophic coccus bacterium in the family Micrococcaceae. Finally, when looking at the API 20E strip none of the results returned positive despite the culture being active and fresh from being streaked recently. Isolates of the M. luteus have been found to overproduce the riboflavin virus when they are grown on toxic organic pollutants like pyridine. Under the microscope they are round cells. 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 Micrococci have been isolated from the human skin, animal and dairy products, and in beer. Micrococcus luteus biochemical test result. [7], In 2003, it was proposed that one strain of Micrococcus luteus, ATCC 9341, be reclassified as Kocuria rhizophila. View Biochemical Tests Lab Report.docx from BIOL 240 at University of Alaska, Anchorage. The positive catalase result lines up with M. luteus (Public Health England). . What are the Uses of Micrococcus Gram Stain? The bacterium also colonizes the mouth, mucosae, oropharynx, and upper respiratory tract. Staphylococcus spp. Your email address will not be published. All three types of hemolytic reactions are represented on this slide. This would be read A/NC. We found this to be true because the filter paper turned blue, which showed that the species has the cytochrome c oxidase enzyme. They also produce yellow or pink colonies when they are grown on the mannitol salt agar, micrococcus flavus, M. terreus, and M. yunnanensis. Three bacteria, E.coli, Staphylococcus epidermis, and Micrococcus luteus, have been grown on TSI or Triple sugar iron agar medium, which is a . 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. Wieser et al. Micrococci can often carry plasmids that provide the organism with useful traits. 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). Micrococcus are aerobic, Gram-positive cocci ranging in size from 0.5 to 2.0 m in diameter. I used Prokka Genome Annotation to identify which genes are present in the bacterium, Kraken Metagenomics to identify what the DNA reads correlated to on different taxonomic levels, and SPAdes Genome Assembler to determine how many contigs were produced from the reads that were produced. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Built with Enlightenment Theme and WordPress. Biochemical Test Chart (You will not fill in every blank in this chart.) This would be read as K/A. Another test I did to identify my isolate was DNA analysis, described in lab handouts 5 and 7. DNA release from the cell is coupled with adsorption of DNA onto a silica spin-column . All pathogenic strains of S. aureus are coagulase positive whereas the nonpathogenic species (S. epidermidis for example) are coagulase negative. Micrococcus luteusare Gram-positive cocci mostly arranged in tetrads and larger than Staphylococcus. In the case of a negative test, no colour change is observed. This can occur due to the presence of a reduced number of proteins that can bind to penicillin. [1] It is urease and catalase positive. This microbe forms large, round colonies. It is essential for differentiating catalase-positive Micrococcaceae from catalase-negative Streptococcaceae. Perkins1, Sarah D., Jennie Mayfield2, and Victoria Fraser3 And. 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.