Question

Please answer the following questions of the genus Salmonella,

1) Describe its

A) colony morphology

B) cell arrangement answer would be: 1) (chains, which includes Diplococcus and/OR Chain of cocci) 2) (Packets) or 3) (Clusters)

2) Information on the different places it can be found (microbiota, environmental, plant symbioses, water systems).

3) EMB is used to Identify fecal coliforms capable of lactose and/or sucrose fermentation what would the results be for Salmonella

a) Growth is Pink. Organism ferments lactose with little acid production (A)

b) Growth is "dark" (purple to black, with or without green metallic sheen), Organism ferments lactose and/ or sucrose with much acid production (A)

c) Growth is "colorless" (no pink, purple, or metallic sheen), Organism does not ferment lactose or sucrose. No reaction (NR)

Answer 1

salmonella is the gram negative bacteria which belongs to the family Enterobacteriacae. It is found in the intestine and feces and causes infection, diarrhea, abdominal pain etc. through contaminated water and food.

Answer 1 (A) The salmonella is the rod shaped bacillus which forms the smooth colonies in the nutrient with a diameter of 2-4 mm

Answer 1 (B) The salmonella either have single cell arrangement or present in pairs such as dipplococcus so the answer is 1) chains like dipplococcus which means in pairs

Answer 2: The genus salmonella is present in the microbiota of intestines of humans and animals which provides the nutritional environment for the growth of the microbe

The salmonella genus is prominent in the natural environment through the the animals and humans waste excreted in the open and due to lack of management of the excreta and sewage.

The salmonella is also found in plant symbiosis . It has mutualistic relationship with aspergillus niger hich is a fungi. It forms the biofilm on the hypae without having any negative impact ans this association promotes the growth of the bacteria

The salmonella is also a major concern in the water bodies due to various reasons such as seawge disposal, by excretion of animals and pollution by humans  

Answer 3 Eosin methylene blue inhibits the growth of the gram positive bacteria and promotes the growth of gram negative bacteria. The organisms which ferments the lactose or sucrorose decrease the ph and the bacterial cell absorbs the purple or black color. But the salmonella is a non fermentor of lactose which means it will not absorb the dye and will form colorless colonies. So the correct answer is (c) Growth is "colorless" (no pink, purple, or metallic sheen), Organism does not ferment lactose or sucrose. No reaction (NR)