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
Scanning electron micrograph of Yersinia pestis, which causes bubonic plague, on proventricular spines of a Xenopsylla cheopis flea. Credit: National Institutes of Health/Department of Health and Human Services (NIAID) 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
Strep agalactiae (Group B Strep) streaked out on Granada plates. Usually this media is used to screen for Group B in pregnant patients, the strep will grow as bright orange colonies while any other growth will be colorless. Perfect for a little Halloween fun...follow me on instagram @stylish_str... Read More
There are many reasons why bacteria evolve resistance to antibacterials, but one of the preventable reasons is the over-prescription of antibacterials to patients who don't have bacterial infections. But how to get people to stop asking for antibacterials? My suggestion is to stop using the wor... Read More
In this short post, I celebrate Valentine's Day with words of light---using bioluminescent bacteria! Read More
Isolated colony of Mycobacterium smegmatis grown on TSA for 96 hrs at 37 degrees C. Margin is lobate with an irregular-rhizoid form. Image taken using transmitted light. 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
In this blog post, I show a science-cartoon by the great "Beatrice the Biologist" that illustrates an important point in my freshman introductory cell and molecular biology course: no matter how tired we might be, we are incredibly busy on a cellular level! Beatrice is a fine artist who underst... Read More
In this blog entry, I explore how students can use their creativity to learn microbiology in innovative and often artistic ways. It makes learning more personal! 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
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.
Microphotograph showing scolex and hooklets of Echinococcus granulosus. Read More
I have found that students become involved, energized, and enthusiastic when I give them opportunities to explore topics in my classes using their own creative approaches and interests. So this semester, in my Biology 111 course at the University of Puget Sound, I found that students explored f... Read More
Tannery tanning fluid sample stained with Live/Dead BacLight under UV light. Either 40x or 100x oil immersion. Green bacteria indicate living cells, while Orange bacteria indicate dead cells. Some of the green cells were moving around even after staining! Read More
Serratia marcescens/Escherichia coli mix grown on TSA for 48 hrs. Serratia marcescens grows red due to prodigiosin and Escherichia coli grows opaque white. Read More
Colorized transmission electron micrograph showing H1N1 influenza virus particles. Surface proteins on the virus particles are shown in black. Credit: National Institutes of Health/Department of Health and Human Services (NIAID). Read More
this is colony pic of T. mantagrophytes grows on dermasel media after 12 days of incubation at 30'C. this study is done for our research work from superfical mycoses s suspected cases.specimens taken from trunk as skin scrapping suspected of T. corporis.microscopic pic of this colony shows p... Read More