Which organism is isolated using 10B broth due to urease activity and alkaline pH?

Which organism is isolated using 10B broth due to urease activity and alkaline pH?

• A. Mycoplasma genitalium
• B. Mycoplasma hominis
• C. Ureaplasma urealyticum
• D. Ureaplasma parvum

Answer: (C)

Urease activity in certain genital mycoplasmas is detected by media that use urea and a pH indicator; when urease-positive organisms grow, they hydrolyze urea to ammonia, raising the pH and causing the medium to alkalinize, which is read as a positive result. 10B broth is such a urease-detection medium. Among the listed organisms, Ureaplasma urealyticum produces urease and is isolated using this type of medium because the enzymatic reaction creates an alkaline environment detected by the test. Mycoplasma genitalium and Mycoplasma hominis do not rely on urease activity for isolation in this medium, so they are not identified by this urease-alkaline pH method. Therefore, the organism best isolated with 10B broth due to urease activity and alkaline pH is Ureaplasma urealyticum.

Urease activity in certain genital mycoplasmas is detected by media that use urea and a pH indicator; when urease-positive organisms grow, they hydrolyze urea to ammonia, raising the pH and causing the medium to alkalinize, which is read as a positive result. 10B broth is such a urease-detection medium. Among the listed organisms, Ureaplasma urealyticum produces urease and is isolated using this type of medium because the enzymatic reaction creates an alkaline environment detected by the test. Mycoplasma genitalium and Mycoplasma hominis do not rely on urease activity for isolation in this medium, so they are not identified by this urease-alkaline pH method. Therefore, the organism best isolated with 10B broth due to urease activity and alkaline pH is Ureaplasma urealyticum.