Question

Why do bacteria regulate virulence gene expression?

At the end of the TCA cycle most of the energy ordinally present in glucose is now found in?

Answer 1

1) Virulence gene expression responds to the fluctuations in environmental conditions which occurs by quorum sensing regulon. Bacteria need to adapt and multiply in varying conditions such as temperature, iron availability, hypoxia or anoxia and oxygen availability etc. Bacteria sense and adapt to low oxygen environments, the presence of reactive oxygen species (ROS) and the presence of nitric oxide by the pathogen upon infection of the host and can lead to changes in gene expression

Quorum sensing involves two component systems, that have one component on the surface of the bacteria which senses environmental changes in pH and temperature. These then transmit through phosphorylation and signals to the transcriptional activator inside the cell that will allow the transcription of genes that will allow the bacteria to live in that environment.

2) Cellular respiration is the oxidation of glucose molecules that results in the production of energy. It starts with break down of one molecule of glucose in the process of glycolysis in cytoplasm, resulting in the formation of 2 molecules of pyruvate and energy as 2ATPs and 2NADH. Pyruvate then undergoes oxidative decarboxylation in mitochondria to form acetyl CoA and 2NADH. Acetyl CoA then undergoes oxidation in mitochondrial matrix releasing enormous amount of energy as 2ATPs, 6NADH and 2FADH2