Question

1. In this experiment, you will set things up again the same way you did in the very first, only this time you will add Mycobacterium tuberculosis instead of yeast. Graph the data as above, and answer the questions below.

Time (minutes)	no sugar	glucose	sucrose	maltose	lactose	galactose
0	0	0	0	0	0	0
5	0	3	0	0	2.8	3.1
10	0	6	0	0	5.6	6.2
15	0	9	0	0	8.8	9.3
20	0	12	0	0	11.5	12.5
25	0	15	0	0	13.9	15.7
30	0	18	0	0	17.2	18.9
35	0	21	0	0	20	22
40	0	24	0	0	23.5	25
45	0	27	0	0	26.5	28.5
50	0	30	0	0	29.5	31.6
55	0	33	0	0	32.3	34.8
60	0	36	0	0	35.2	37.8

a) What do you notice immediately about sugar utilization in M. tuberculosis?

b) Consider each sugar carefully, and provide a possible explanation for each of them. You may want to refer back to the structures of the sugars provided at the beginning.

Answer 1

a) Glucose, lactose and galactose used as a energy source by M.tubercolosis. Galctose metabolism is greater than glucose and lactose. sucrose and maltose are not used as a energy source by M.tubercolosis.

b)Glucose: In M.tubeculosis glucose is best carbon source to provide faster growth but it required the c-AMP to utilised the glucose. thats why growth is slow in glucose containing media as compare to galactose containig media.

Sucrose: Sucrose is a diassacharide (Non-reducing sugar)form of glucose and fructose and uptake of sucrose take place by sucrose permease which is not present in M.tubeculosis. Sucrose is not utilised as a carbon source by M.tuberculosis and No growth is observed in sucrose containing media.

Maltose : Maltose  is a diassacharide (reducing sugar) form of two glucose unit bond  with alpha 1-4 and catabolised with enzyme Maltase which is present in germinating seeds and uptake of maltose take place by maltose permease which is not present in M.tubeculosis. maltose  is not utilised as a carbon source by M.tuberculosis and No growth is observed in maltose containing media.

Lactose: Lactose is a diassacharide of one unit of glucose and galactose. Lactose is utilised as a carbon sourse by activating Lac operon which transport and metabolised lactose in M.tubeculosis by synthesising  the series of enzyme ,betta -galactosidase cleave the lactose into glucose and galactose , galactose permease trasport the lactose inside the cells and Galactoside acetyltransferase which transfer the aacetyl group from acetyl CoA to B-galactosides). By the Lac operon M.tuberculosis utilised the lactose as a carbon sourse for growth and growth is obeserve in lactose containing media.

Galactose: Galactose is a monossacharides  use as a carbon source to provide bacterial growth .Fast growth is observed in galactose containing media.