A curved Gram-negative rod that is nonfermentative and nitrite positive is probably which organism?

The organism described in the question as a curved Gram-negative rod that is nonfermentative and nitrite positive corresponds to Campylobacter jejuni. This bacterium is known for its characteristic curved shape and is classified as a nonfermentative organism, meaning it does not ferment carbohydrates to obtain energy.

A notable characteristic of Campylobacter jejuni is its ability to reduce nitrate to nitrite, which is significant in differentiating it from other similar organisms. Campylobacter jejuni is commonly associated with gastrointestinal infections and is often found in undercooked poultry and contaminated water.

Other organisms listed such as Vibrio cholerae and Helicobacter pylori do not completely match the description. Vibrio cholerae, while a curved Gram-negative rod, is associated with cholera and is fermentative, particularly with sucrose. Helicobacter pylori, although it is a curved Gram-negative rod, is also not typically tested for nitrite reduction in the same context as nitrates. Salmonella typhi is a straight rod rather than a curved one, and it does not have the same characteristics of being nonfermentative.

In summary, the specific traits of being a curved Gram-negative rod, nonfermentative, and nitrite positive