Question

With regards to microbiology, what is differentiation? What does it mean to be terminally differentiated?

Answer 1

In general for Cell Biology, Cellular differentiation is a process by which a primitive, unspecialized cell become specialized in their morphology and physiological status in a specified organism, to carry out distinct function. A stem cell is an unspecialized cell that can divide indefinitely as needed and can, under specific conditions, differentiate into specialized cells. The capacity of their development termed as ' potency '. So, the Stem cells can be Totopotent, Pluripotent or Multipotent in nature. Where as,  a unipotent cell is fully specialized and can only reproduce to generate more of its own specific cell type, and can perform only specialized function. Such state of these unipotent cells are called 'Terminally differentiated' .

But, if we consider microbiological aspect, Differentiation deals with the identification of the procaryotes depending on their morphological features, metabolic properties, pathogenicity, nutritional requirements, staining reactions and antigenic properties.

As an example, we can use the table to differentiate between, enteric bacteria, vibrios, and pseudomonads -
But Terminally differentiated term does not specify any different meaning in microbiology. This is the same totally differentiated state of cells destined to fulfil specific function, just as mentioned in earlier.