it was found that in the pH domain 6.7-8.6 frequently used in experiments involving hen lysozyme, the pH optimum of lysis of Micrococcus luteus cells at low ionic strength (0.02-0.05) by the high-temperature form (40 degree C, physiological temperature) was one to two pH units lower than that by the This category includes acidophiles, thermophiles, osmophiles, Actinobacteria -> Mesophiles = 0, Extremophile = 1, Negative = 0, Positive = 1, Indeterminate = 2, Microbes that live anywhere in the human body and are not pathogenic to humans (i.e. Newly discovered hazards are frequent and this information may not be completely up to date. It has also been isolated from … Further this activity is exhibited in a wide range of salinity from 0-30 ppt with optimum lytic activity observed at around 20 ppt. M. luteus has been reported as the causative agent in cases of intracranial abscesses, pneumonia, septic arthritis, endocarditis, and meningitis(2). They can even survive in conditions that have very little of even no oxygen, using glycolysis and alternative electron acceptors to create ATP. It showed highest (99.7 %) 16S rRNA gene sequence similarity with Micrococcus yunnanensis YIM 65004T followed by Micrococcus luteus NCTC 2665T (99.6 %) and Micrococcus endophyticus YIM Journal of Infection and Chemotherapy : Official Journal of the Japan Society of Chemotherapy 15(6):424-5. Their optimal pH is in the alkaline range, and most are very sensitive to low pH and salt. Penicillin acylse was more active against ampicillin. However, CA from M. luteus was stable in the pH and temperature range of 7.5–10.0 and 35–55 °C, respectively. for which no prophylaxis is known. Extracellular proteinases are produced by several species of ‘micrococci’, although their activity is optimal in an alkaline pH range, being almost negligible at pH values below 5.5. It is urease and catalase positive. Colony Morphology: yellow round smooth umbonate opaque dull Cellular Morphology: coccus tetrads Gram-positive. SUSCEPTIBILITY TO DISINFECTANTS: Gram-positive bacteria are generally susceptible to a number of disinfectants, including phenolic compounds, hypochlorites (1% sodium hypochlorite), alcohols (70% ethanol), formaldehyde (18.5 g/L; 5% formalin in water), glutaraldehyde, iodines (0.075 g/L)(7). This strain was previously designated as a quality-control strain in a number of papers and it is also cited as the standard culture in several official Results . concentrations [10 % (w/v) NaCl], temperatures of 15–41 6C and a pH range of 5–12. They are found on the skin of humans and other animals and in soil, marine and fresh water, plants, fomites, dust, and air(2,3). They have been shown to persist on human skin for extended periods of time ranging from few months to at least one year (up to two and a half years for several strains of M. luteus)(3). It can grow at 45°C and in 10% Sodium Chloride. The kinetics of lysis of Micrococcus luteus by hen egg-white lysozyme in dilute buffer media is characterized by pronounced substrate inhibition. All the … 0000002602 00000 n Description: Micrococcus luteus (M. luteus) is a Gram-positive to Gram-variable, non-motile, coccus, saprotrophic bacterium. If two far ranges of temperatures pH before sterilisation: 7.8 Usage: Maintenance and taxonomy (e.g. SYNONYM OR CROSS REFERENCE: M. luteus, M. lylae, M. antarcticus, and more recently M. endophyticus, M. flavus, M. terreus, and M. yunnanensis. belonging to a recognized group of disease-invoking agents in humans or animals and having an enzyme is active over a broad pH range (6.0–9.0). This effect occurs within the complete pH range where lysozyme activity is detectable. From the growth profile, M. luteus strain BAA2 attained the maximum growth at 30 h of incubation (Figure 3B). neutral to slightly alkaline pH and within 60 to 80oC. SYNONYM OR CROSS REFERENCE: M. luteus, M. lylae, M. antarcticus, and more recently M. endophyticus, M. flavus, M. terreus, and M. yunnanensis. They have also been isolated from blood and surgical specimens in some patients with coronary and infectious conditions(3). RISK GROUP CLASSIFICATION: Risk Group 1(10). Its optimal temperature range for growth is 25° to 37°C. Schroeter 1886, Micrococcus lysodeikticus Fleming 1933, "not Micrococcus luteus" Lehmann and Neumann 1896. Gloves when direct skin contact with infected materials or animals is unavoidable(11). extended history of safe usage and 4 being a species that can cause a very serious human disease, Bacteria; Actinobacteria; Actinobacteria (class); Actinobacteridae; Actinomycetales; Micrococcineae; Micrococcaceae Allow sufficient contact time before clean up(11). Description: Micrococcus luteus (M. luteus) is a Gram-positive to Gram-variable, non-motile, coccus, saprotrophic bacterium. The change in pH was observed at every 3 h interval during the growth of M. luteus strain BAA2 (Figure 3A). capable of Copyright © No = 0, Yes = 1. Note: Tang and Gillevet, propose to reclassify the ATCC 9341 strain as Kocuria rhizophila. The activity of lysozyme is a function of both pH and ionic strength. If the species was not widely studied, the American Type Culture Collection (ATCC) was used to determine the optimal pH for storage. No = 0, Yes = 1, Does the species causes disease in animals? Colony Morphology: white top round smooth … The optimal temperature at which this species grows. If the species was not widely studied, the SURVIVAL OUTSIDE HOST: Micrococci are relatively resistant to drying and to moderate temperature changes(2). The extended preservation capacity up to pH 6.5 makes SA superior over other commonly used preservatives such as propionates and benzoates (6). This risk group applies to the genus as a whole, and may not apply to every species within the genus. List of Bacterial Names with Standing in Nomenclature. It will grow on a variety of media including Tryptic Soy Agar, Standard Methods Agar, Nutrient Agar, and Sheep Blood Agar. Micrococcus (mi’ krō kŏk’ Əs) is a genus of bacteria in the Micrococcaceae family. Sccharomyces cerevisiae . were determined, the average was taken. It can form in tetrads or irregular clusters but not in chains and belongs to the family Micrococcaceae. DISPOSAL: Decontaminate, either by steam sterilization, incineration, or chemical disinfection, before disposal(11). Former members of the genus Micrococcus, now assigned to other genera, include Arthrobacter agilis, Nesterenkonia halobia, Kocuria kristinae, K. rosea, K. varians, Kytococcus sedentarius, and Dermacoccus nishinomiyaensis (1,2). M. morrhuae K-17 grows well in a synthetic medium (SM-1) which contains a number of salts, 0.21 M KCl, 2 M NaCl, D-mannose, five vitamins and ten amino acids. CONTAINMENT REQUIREMENTS: Containment Level 1 facilities, equipment, and operational practices for work involving infectious or potentially infectious materials. halophiles, oligotrophs, and others. Most natural environments have pH values between 5 and 9, and organisms with pH optima in this range are most common. PHYSICAL INACTIVATION: Bacteria are generally sensitive to moist heat and dry heat(8) . Transmission usually occurs through contaminated surfaces and/or objects. They are catalase positive, oxidase positive, indole negative and citrate negative. Growth of micrococci may be significantly reduced at temperatures >45 °C, pH <6, and in high salt concentrations (>15%)(9). Isolates from these and other similar dry cured meats are ascribed to the genera Staphylococcus and Micrococcus. COGEM released a comprehensive database of pathogenicity assessment of around 2575 bacterial MODE OF TRANSMISSION: Transmission is possible through contact with contaminated objects and/or surfaces (demonstrated by bacterial transfer associated with paper-towel dispensing)(4). Micrococcus luteus. Micrococcus luteus. Bacillus cereus. can be isolated from biological samples (taken from skin) using culture techniques (on agar media)(2,3). M. luteus is most common and is found in nature and in clinical specimens. Micrococcaceae -> Note: All diagnostic methods are not necessarily available in all countries.