Streak plate isolation of E. coli on MacConkey Agar grown for 24 hrs at 37 degrees. E. coli demonstrates strong lactose fermentation indicated by the bright pink halo, bile precipitant around the colonies, and pink colony growth. Read More
Colorized scanning electron micrograph of filamentous Ebola virus particles (blue) budding from a chronically infected VERO E6 cell (yellow-green).
Photo taken from NIAID flicker Read More
Starch agar contains high molecular weight starch molecules (soluable starch). When Iodine is added it reacts with starch to produces a dark brown/purple color. A zone of clearing forms around organisms that produce the exoenzyme amylase after addition of iodine. This plate was incubated for ... Read More
Physarum polycephalum, slime mold, grown in a large perti plate on moist paper towels using oatmeal as the food source. Culture was grown in the dark at room temperature. The paper towel was moistened every day with tap water. After 3 week’s the culture formed sporangia (fruiting bodies). Im... Read More
Mannitol Salt Agar (MSA)
•Important Ingredients: Phenol red, mannitol (sugar), 7.5% NaCl
•Differential: between pathogenic S. aureus and S. epidermidis
•Selective: NaCl inhibits non-halophilic organisms. Organism that can grow are halophilic.
•Mannitol Fermentors: fermentation of acid cau... Read More
Growth of Streptococcus mitis on blood agar demonstrating alpha hemolysis seen as a greenish color around the growing colonies due to a reduction of the hemoglobin to methemoglobin in the surrounding agar. Image taken using transmitted light. Read More
Many air travelers are concerned about the risks of catching a disease from other passengers given the long time spent in crowded air cabins. New research shows disease-causing bacteria can linger on surfaces commonly found in airplane cabins for days, even up to a week. Participants discuss ... Read More
Nocardia asteroides isolation from blood specimen. On culture, chalky white colonies were seen on blood agar. Image courtesy MicrobeWorld user Kyriakos Zaragkoulias, Specialty Registrar (StR) in Medical Microbiology at General Hospital of Thessaloniki “G. Papanikolaou”, Greece.
Unknown organism isolated from a swab taken off the bottom of a shoe. Students were asked to swab something in the classroom. One swab was done on the bottom of a shoe and incubated on a TSA plate for 48 hrs at 37 degree’s C. The organism was difficult to scrape so a small chunk of the organis... Read More
Acid Fast stain done on a mix of Staphylococcus aureus and Mycobacterium smegmatis. Carbol fuchsin was applied to the smear and set over a steaming water bath for 10 min to help penetrate the mycolic acid in the cell wall, then rinsed with acid alcohol which washes the carbol fuchsin out of al... Read More
The following picture shows the isolated black colonies of Salmonella on Salmonella-Shigella (S-S) Agar. S-S Agar is used as a selective and differential medium for the isolation of Salmonella and some Shigella species. The inclusion of bile salts is to inhibit gram-positive organisms. Ferric ci... Read More
Gram stain of B. subtilis showing characteristic G +streptobacillus morphology. Read More
Bacitracin test done on a lawn of Streptococcus pyogenes grown on blood agar. The zone of inhibition around the bacitracin disc, approx 14mm measuring the entire length of the zone, indicates sensitivity. The zone of inhibition is red because the red blood cells did not lyse. Grown for 24 hr... Read More
This is an 3D image of conidiophores of the filamentous fungus Neurospora crassa. Conidiophores are hyphae which differentiate to produce asexual structures named spores or conidia. The image taken using a confocal microscope shows conidiophores stained with a fluorophore which stains components... Read More
This is a picture of Echinococcus granulosus from an infected liver specimen recently received in our laboratory. It is pictured in a saline wet mount at 40X magnification. The picture shows an evaginated scolex from an immature worm with hooklets.
The adult worm of Echinococcus granulosus l... Read More
Three organisms inoculated in TSB to look at tube morphology. From left to right:
Staphylococcus aureus: flocculent growth/turbid, growth throughout the tube.
Mycobacterium smegmatis: pellicle, growth at the top of the tube. M. smegmatis tends to stick to the tube and grow up the side.
Ba... Read More
This episode: Bacteria are important for a good immune response to unadjuvanted influenza vaccines!
(14.6 MB, 16 minutes)
A streak plate of Strep pyogenes on blood agar, stock culture used for class, was kept at room temp for 1 month. Before disposal a contaminant, presumably environmental, was seen on the plate. The pigment was opaque tan/yellow and with a mucoid surface. Lobate marigins with raised irregular-rh... Read More
The campaign is called "Kick Back Ebola." But the posters pack a punch.
Sierra Leone has reported over 700 suspected Ebola cases, more than any other country this year. To help stop the outbreak, health workers have put up Ebola awareness signs all over Sierra Leone's seaside capital of Freet... Read More