A clinical laboratory receives a cerebrospinal fluid (CSF) sample from a 65-year-old patient presenting with fever, headache, and nuchal rigidity. Gram stain reveals Gram-positive cocci in pairs and short chains. Culture on blood agar grows alpha-hemolytic colonies that are optochin-susceptible and bile soluble. Which organism is most likely identified?

What is the most appropriate method for sterilizing a heat-labile liquid solution containing essential proteins for use in tissue culture?

A clinical microbiology laboratory isolates a Gram-negative rod from a wound infection following a dog bite.
The organism grows on MacConkey agar, is oxidase-positive, and produces a characteristic bleach-like odor.
The MOST likely identification is:

During the investigation of a foodborne illness outbreak linked to raw sprouts, several bacterial isolates are obtained from patient stool samples and the implicated food source. Which of the following molecular methods would be MOST useful for establishing a definitive link between the clinical isolates and the food isolate?

In a clinical microbiology laboratory, quality control testing of Mueller-Hinton agar used for disk diffusion susceptibility testing involves checking the zone sizes for E. coli ATCC 25922, S. aureus ATCC 25923, and
P. aeruginosa ATCC 27853. What is the primary purpose of including P. aeruginosa ATCC 27853 in this QC?