The production of Metallo-β-lactamase is one of the resistance mechanisms of Pseudomonas aeruginosa. Metallo-β- lactamases are members of Group B in the molecular classification of Ambler and are Clavulanic acid resistant enzymes which require divalent cations of zinc as co-factors for enzymat... Read More
I am just submitting this as a test submission so that I know how the whole process functions.
Image taken at Pashupathinah Temple in Kathmandu Nepal using a Nikon PS510 Read More
Organisms grown in Fluid Thioglycollate Media w/out resazurin dye is a reducing media that uses sodium thioglycollate to chemically combine with dissolved oxygen to deplete the oxygen in the media. All organism except for Neisseria sicca were grown for 48 hours at 37 degrees C. Neisseria sicca i... 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
Kirby-Bauer disk diffusion susceptibility test on coagulase-negative Staphylococcus aureus and E.coli grown on Mueller-Hinton agar with tetracycline (30 µg), cephalothin (30 µg), erythromycin (15 µg), chloramphenicol (30 µg), vancomycin (30 µg), penicillin (10 µg), streptomycin (10 µg), and novo... Read More
As my Fall semester approaches, I am reflecting on last Fall. I taught a freshman seminar course revolving around symbioses and parasitism, and was fortunate to have many well known scientists be willing to "virtually visit" my class! Here is my report from last year on the great Jack Gilbert.... Read More
Scanning electromicrograph of Staphylococcus aureus bacteria. Credit: National Institutes of Health/Department of Health and Human Services (NIAID). Read More
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
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
A quick demonstration of how my Microbial Mania can impact the holiday season! 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
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
Please help me! I am planning to identify this microorganism by API but I can not identify the shape (rod or cocci). This microorganism has positive oxidase. Its colony is red, irregular, flat.
Please teach me. Thanks so much! Nhu Thuy from Vietnam
This confocal micrograph, taken as part of a synthetic biology project, shows Bacillus subtilis, a Gram-positive, rod-shaped bacterium that is commonly found in soil. Distinct lineages of bacteria expressing different fluorescent proteins were initially mixed randomly on a petri dish. As the bac... Read More
Gram stain done on S. pyogenes showing the characteristic long G+ streptococcus chains. Culture grown on blood agar for 48 hrs at 37 degree’s C. 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
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
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