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
Some holiday fun from last winter composed of different collected plate contaminants. Based on colony morphology and wet mounts, these bacteria are likely to be: Staphylococcus sp. (white), Serratia marcescens (dark orange), and Micrococcus luteus (creamy yellow). The design was incubated for 5-... Read More
A team of European scientists say they have discovered a compound that can prevent the spreading of coronaviruses, responsible for the SARS and MERS outbreaks that have killed about 1,000 people worldwide.
A team of scientists led by Edward Trybala from the University of Gothenburg in Sweden,... Read More
Could a fist bump be a cleaner, better way for people to greet each other, especially in germy hospitals? British researchers have done an experiment that seems to say yes.
They tested just how many bacteria are transferred hand to hand during a handshake, a high-five and a fist bump. Handsha... 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
Ten years ago this month I wrote the first post at virology blog, entitled Are viruses living? Thanks to EE Giorgi for pointing out the ten year anniversary, and also for publishing an interview with me at her blog, Chimeras. Here is how this blog got started. Read More
I have just finished listening to TWiM 92 and it was very interesting, as always. It is a pleasure to listen to all of you discuss these fascinating topics.
At the end of this episode, you talk about probiotics because it w... 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
Vincent visits the Australian Animal Health Laboratory in Geelong, Australia and speaks with Linfa about his work on bats and bat viruses.
Hosts: Vincent Racaniello
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
The TWiVome discusses an miRNA based strategy to mitigate risk of gain of function studies, and identification of a second receptor required for Lassa virus entry.
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 episode: Microbes in the human gut seem to prevent/inhibit cholera!
(10.5 MB, 11.5 minutes)
Hello TWiM team,
Many people have heard that human urine is devoid of germs, but a new study seems to question that idea.
"Doctors have been trained to believe that urine is germ-free," Dr. Linda Brubaker, dean of Loyola University Chicago Stritch School of Medicine, said in a university news release. "These ... 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.
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
Gram stain of B. subtilis showing characteristic G +streptobacillus morphology. Read More