Question

Of the following choices, what two species could be distinguished with kligler's iron agar?

a. gram- e. coli and gram- salmonella
b. gram- e. coli and gram s. aureus
c. gram streptococcus and gram staphylococcus
d. none of these could be distinguished by kia

Answer 1

Kligler's Iron Agar can distinguish between gram-negative Escherichia coli and gram-negative Salmonella, as E. coli will produce pink colonies and Salmonella will produce colorless colonies with a potential black precipitate.

Step-by-step explanation:

Of the following choices, the two species that could be distinguished with Kligler's Iron Agar (KIA) are gram-negative Escherichia coli and gram-negative Salmonella. KIA is designed to differentiate members of the Enterobacteriaceae family, which are gram-negative bacilli, based on their ability to ferment glucose and lactose, and to produce hydrogen sulfide. E. coli, being a lactose fermenter, will produce pink colonies on KIA, while Salmonella, which does not ferment lactose, will produce colorless colonies with a black precipitate if it produces hydrogen sulfide.

The culture characteristics on KIA allow laboratory technicians to distinguish between these two common gastroenteritis-causing bacteria. This is because KIA medium provides not just selective growth conditions but also diagnostic clues based on the metabolic properties of the bacteria being tested.