micrococcus luteus biochemical tests

Depend on Gram stain Test and Biochemical Test find four species of cellulolytic bacteria such as Bacillus subtilis, Pseudomonas diminuta, Micrococcus luteus and Plesiomonas shigelloides. Beta-hemolysis is a defining characteristic of Staphylococcus aureus and a certain streptococci. Shape (Cocci/Diplococci/Rods) Cocci. The pathogen, Staphylococcus aureus, is notably coagulase-positive while most other members of the family are coagulase-negative. Another test I did to identify my isolate was DNA analysis, described in lab handouts 5 and 7. Alpha-hemolytic colonies often assume a greenish hue. 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. These residential skin organisms are also fairly ubiquitous in the environment. 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. Basics of Differentiation of Gram Positive Cocci, The Journal of Applied Laboratory Medicine, Challenges in Blood Group Alloantibody Detection, Clinical Applications of Complement Testing, Collecting Blood from Patients with Vascular Lines, Diagnosis of Syphilis Using the Reverse Algorithm, Liquid Chromatography LC Basics and Separation Techniques, Liquid Chromatography Separation Mechanisms, Optimal Reporting of Diagnostic Accuracy Studies, Pharmacogenetics for Drug Hypersensitivity Reactions, Sensitivity Specificity and Predictive Values in Diagnostic Testing, Transfusion Support in Hematopoietic Cell Transplant, Clinical Chemistry Guide to Scientific Writing, Commission on Accreditation in Clinical Chemistry. Bacillus megaterium fermented sugars but didn't grow in the anaerobic area of the butt. They are also catalase-positive and often weakly oxidase-positive ( modified oxidase test positive). The metabolic pathways required for biomass production in silico were determined based on earlier models of actinobacteria. In the case of a negative test, no colour change is observed. 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. Micrococcus Public Health Agency of Canada., Public Health England. The fluid thioglycallate test showed that the bacteria was an obligate aerobe because the growth was concentrated at the top of the tube in the pink region. Enterococcus spp. [1] It is urease and catalase positive. Bacteria Detail., The Editors of Encyclopdia Britannica. 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. 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. It has been isolated from human skin. [2] It resists antibiotic treatment by slowing of major metabolic processes and induction of unique genes[citation needed]. 2019). If the agar plate is held up to a light source, you can sometimes see through the agar, as is pictured on the left. 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. The first control consisted of plates of agar-agar to test sterility. In Wikipedia, The Free Encyclopedia. The microbiome of the nasal cavity can also change in response to environmental factors such as geographic location, and hygiene (Rawis et al. Though not a spore former, the Micrococcus cells can survive for an extended period of time, both at refrigeration temperatures and in nutrient-poor conditions such as sealed in amber. They can be found in boiling hot springs; they can be found in frigid waters in the artic. Micrococcus luteus is coagulase negative, bacitracin susceptible, and forms bright yellow colonies on nutrient agar. The microscopic morphology of the organisms as visualized using the Grams stain can give initial clues as to the possible identification of the organism. [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]. Production of bubbles indicates a positive reaction. Abstract Micrococcus luteus IFO 3333 cells, both treated with chemical reagents and non-treated, were observed with a scanning electron microscope (SEM). The tetrads of the micrococci, the grape like clusters of the staphylococci, and the pairs and/or chains of the streptococci are shown. This matches up with the PATRIC metagenome binning which also showed some impurities (Figure 1). Staphylococcus aureus. 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. The staphylococci and micrococci are catalase producers while the streptococci, enterococci, and a variety of other Gram-positive cocci are catalase-negative. Wikipedia also says that Micrococcus luteus is an obligate aerobe, backing up what my results show (2019). 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. 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. Growth or weak growth is observed at 45C, at pH 10, and in the presence of 10% sodium chloride (NaCl). Micrococcus luteus is a Gram-positive to Gram-variable, nonmotile, tetrad-arranging, pigmented, saprotrophic coccus bacterium in the family Micrococcaceae. See answer (1) best answer. I then streaked the exposed swab onto a petri dish to allow the organisms to grow, incubating them at 25 degrees Celsius in a dark cabinet. Catalase test was the first biochemical test to be done . 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). They are positive for catalase and oxidase ( modified). Whereas the M. variant has a G-C content of about 66-72mol%. They contain cytochromes and are resistant to lysostaphin. From four species that have been identify, only Bacillus subtilis and Pseudomonas diminuta that show ability to block pathogen bacteria Edwardsiella tarda. When looking at the genetic tests, most of the identified strains in the Korona test are Micrococcus luteus. // Micrococcus luteus is generally harmless but can become an opportunistic pathogen in immunocompromised people or those with indwelling catheters. 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). The agglutinability of the cells with antiserum containing anti-teichuronic acid antibody was examined. The bacterium also colonizes the mouth, mucosae, oropharynx, and upper respiratory tract. 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. 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. In the final section of a study, it is essential to present important information, techniques, and variables. As the microbe is gram positive this means that it has a large peptidoglycan layer and lacks a lipopolysaccharide layer. U.S. 2022 American Association for Clinical Chemistry. For the detection of oxidase enzyme, filter paper circular disks impregnated with tetramethyl-p-phenylenediamine dihydrochloride in dimethyl sulfoxide are used. The GC content of the DNA ranges from about 65 to 75 mol%. With the advent of newer molecular techniques, genus and species confirmation is even faster and easier. Micrococcus luteus are Gram-positive cocci mostly arranged in tetrads and larger than Staphylococcus. Washington, DC 20001 Growth can produce colonies of a certain size and consistency, as well as pigmentation. This technique is centered on the performance of the classic Grams stain. Welcome to this Pearl of Laboratory Medicine on Basics of Differentiation of Gram-positive Cocci.. They are generally strict aerobes and these can generally reduce nitrate concentration. Lastly, do not underestimate the variety of different genera in the four families of the Gram- positive cocci that can, under the right circumstances, move from relatively harmless saprophytes to disease-producing opportunists. Biochemical Test Chart (You will not fill in every blank in this chart.) 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. They are positive for catalase and oxidase ( modified). Annals of Allergy, Asthma and Immunology 122(1):17-24. I think based on all this information, that my microbe is in fact micrococcus luteus as suggested by the PATRIC metagenome binning test, and the krona (Figure 1). 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. Cells are catalase positive, oxidase positive, and exhibit strictly aerobic metabolism. 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. After observation of the colony and microscopic morphology, the production of catalase by the isolate is documented. 2. All three types of hemolytic reactions are represented on this slide. Know more about our courses. M. luteus present on the human skin can transform compounds present in sweat into compounds with an unpleasant odour. Luteus is an obligate aerobe (medical. The MacConkey agar is selective for gram-negative which is why my microbe didnt show much growth on it, and because it didnt change colors it means it didnt ferment the lactose. 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. M. luteus has one of the smallest genomes of all the bacteria. Intermediates or end products of these varied metabolic activities can be detected by performing biochemical assays on a bacterial culture. Three bacteria, E.coli, Staphylococcus epidermis, and Micrococcus luteus, have been grown on TSI or Triple sugar iron agar medium, which is a . Required fields are marked *. If acid is produced, the pH indicator will turn yellow. A very important test in the categorization of the staphylococci is the coagulase test. luteus is rarely found to be responsible for infections. (2019, March 14). They grow in circular, entire, convex, and creamy yellow-pigmented colonies with diameters of approximately 4 mm after 2-3 days at 37C. Following incubation at 37oC, if the plasma forms a clot, the organism is coagulase positive. The kaiju metagenome binning shows that the microbe sample is not completely pure (Figure 2). 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. View Online Copy of Unknown ID Chart.xlsx from BIOL 250L at University of South Carolina. 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. Colony pigmentation varies considerably but is usually different shades of yellow or cream-white. Some of the Micrococcus are pigmented bacteria, for example, M. roseus produces reddish colonies and M. luteus produces yellow colonies. Many members of the genus have been reclassified into other genera. This bacterium can withstand massive doses of UV radiation and it also has the capability to degrade certain pollutants such as petrol. Similar to the situation in the prosthetic valve endocarditis that is caused by more aggressive and highly resistant bacteria. As its name suggests, mannitol salt agar (MSA) contains 1% mannitol (sugar), 7.5% salt, and agar as a solidifying agent. Label the slide with the name of the organism; Place 15 - 20 uL of the culture in the middle of the slide 2014). 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. all 3 tests done w/SIM deeps just add Kovac's reagent for Indole test Alcaligenes faecalis (left) - . Micrococcus lylaeare Gram-positive cocci mostly arranged in tetrads. The oxygen class and the gram positiveness of the microbe also matches up with that of Micrococcus luteus. . 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. It has survived for at least 34,000 to 170,000 years, as assessed by 16S rRNA analysis, and possibly much longer. Staphylococcus spp. They are found in many other places in the, M. luteus has one of the smallest genomes of all the bacteria. Hybridization studies indicate that species within the genus Micrococcus are not closely related, showing as little as 50% sequence similarity. They are fairly small as well, usually about a millimeter in diameter and of a normal height. 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. The micrococci produce tetrads consisting of 4 cocci clustered together. Under the microscope they are round cells. They are seldom motile and are non-sporing. Benecky M. J.; Frew J. E.; Scowen N; Jones P, Hoffman B. M (1993). They are indole negative, oxidase-positive, catalase-positive, and citrate negative. 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. M. luteus is found in the soil, dust, water, and human skin flora. A rare case of prosthetic valve endocarditis is caused by Micrococcus luteus, it is described and compared with the few cases that are reported in the literature, as well as the clinical features, microbiological profile, therapy, and prognosis of common prosthetic valve endocarditis. The species Micrococcus luteus (Schroeter 1872) Cohn 1872 (Approved Lists 1980) emend. There are around nine species that are recognized in the genus. Finally I used different antibiotic disks to check for its resistance to antibiotics, using Gentamicin, Cefoperazone, Vancomycin, Tobramycin, Amikacin, Trimethoprim, Oxacillin, and Cefazdin. Only the Micrococcus luteus species contained cytochrome c oxidase. 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. A positive test leads to the development of blue or purple-blue on the disc within two minutes. It grew in circular, entire, convex and creamy yellow pigmented colonies heaving 0.5-2.5 diameter. 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. 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. 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 streptococci and enterococci are categorized by expression of either beta, alpha, or gamma hemolysis on sBAP, depending on the genus/species. If an organism is capable of fermenting the sugar glucose, then acidic byproducts are formed and the pH indicator turns yellow.