Abiotrophia (nutritionally variant streptococci) require which nutrient for growth?

Abiotrophia (nutritionally variant streptococci) require which nutrient for growth?

• A. Heme
• B. Vitamin B12
• C. Pyridoxal
• D. Thiophene-2-carboxylic hydrazide

Answer: (C)

Some bacteria have specialized growth needs, and Abiotrophia, the nutritionally variant streptococci, require pyridoxal (vitamin B6) to grow. On routine media they may not grow well or at all, but providing pyridoxal or using enriched media allows colonies to form. This dependence on a specific growth factor is why they’re described as nutritionally variant and are often harder to culture. The other options don’t supply the nutrient these organisms need: heme is a growth factor for Haemophilus, vitamin B12 supports other bacteria, and thiophene-2-carboxylic hydrazide isn’t a growth factor for these organisms.

Some bacteria have specialized growth needs, and Abiotrophia, the nutritionally variant streptococci, require pyridoxal (vitamin B6) to grow. On routine media they may not grow well or at all, but providing pyridoxal or using enriched media allows colonies to form. This dependence on a specific growth factor is why they’re described as nutritionally variant and are often harder to culture. The other options don’t supply the nutrient these organisms need: heme is a growth factor for Haemophilus, vitamin B12 supports other bacteria, and thiophene-2-carboxylic hydrazide isn’t a growth factor for these organisms.