Question

11.(3 pts) Consider what would happen to a gram-positive bacterium that could no longer link glucose monomers together to form insoluble glycogen granules.

Draw an “X” on the line next to the each of your predicted outcome(s) for the cell.

______ The osmotic pressure will increase inside the cell, cause it to lyse

______ The cell will be more susceptible to periods of carbon starvation

______ The cell will grow at a faster rate using the free glucose monomers

Explain your answer(s) and how you eliminated the unlikely outcome(s).

Answer 1

Glycogen is a polysaccharide of glucose. It is one of the key storage molecule alongwith polyhydroxy butyrate (PHB)

The first statement is true if glucose concentration is high (Carbon abundance) and Glycogen synthesis can not happen then cell will lyse due to osmotic pressure as bacterial cell does not have any transporter to pump out the sugar against the gradient from the cytoplasm

2nd statement is true, as glycogen is a key storage compound. It is utilized during period of carbon starvation. During period of nutrient limitation, glycogen is hydrolysed to yield glucose monmers by cleaving of alpha 1,4 and alpha 1,6 glycosidic bonds. faulty glycogen synthesis makes the cell ill prepared to face carbon starvation.

Third statement is False as each bacterial cell has it's own specific doubling time. Abudance of carbon can in no way reduce the doubling time. However opposite can be true. Cell doubling or growth involves several steps like DNA replication, increase in cell size. Carbon abundance can not fasten DNA replication in any way.