Penicillin is produced by P. chrysogenum in a fed-batch culture with the intermittent addition of glucose solution to the culture medium. The initial culture volume at quasi-steady state is V0 = 500 l, and glucose-containing nutrient solution is added with a flow rate of F = 50 l/h. Glucose concentration in the feed solution and initial cell concentration are S0 = 300 g/l and X0 = 20 g/l, respectively. The kinetic and yield coefficients of the organism are mm = 0.2 h-1 , KS = 0.5 g/l, and YX/S = 0.3 g dw/g glucose. Determine the concentration of cells at quasi-steady state when t = 10 h.

#Question id: 10340

#SCPH05 I Biotechnology

There several charecteristics of nitrate reductase, which of the following properties of nitrate reductase is incorrect?

#Question id: 10340

#SCPH06 I Botany

There several charecteristics of nitrate reductase, which of the following properties of nitrate reductase is incorrect?

#Question id: 10341

#I Life Science/ Life Sciences Group – I-V

The accumulation of nitrate that results from diminished nitrate reductase activity, this symptoms is caused by

#Question id: 10341

#SCPH05 I Biotechnology

The accumulation of nitrate that results from diminished nitrate reductase activity, this symptoms is caused by

#Question id: 10341

#SCPH06 I Botany

The accumulation of nitrate that results from diminished nitrate reductase activity, this symptoms is caused by

#Question id: 10342

#I Life Science/ Life Sciences Group – I-V

Nitrate reductase is an important enzyme for nitrate assimilation. Given below some regulation of nitrate reductase activity through phosphorylation and dephosphorylation.

a) Light, and other environmental factors stimulate a protein phosphatase that dephosphorylates a key serine residue in the hinge 1 region of nitrate reductase and thereby activates the enzyme

b) In Dark, and Mg2+ stimulate a protein kinase that phosphorylates the same serine residues, which then interact with a 14-3-3 inhibitor protein, and thereby inactivate nitrate reductase

c) In Light, and Mg2+ stimulate a protein kinase that phosphorylates the serine residues, and thereby activate nitrate reductase

d) In Dark, and other environmental factors stimulate a protein phosphatase that dephosphorylates a key serine residue in the hinge 1 region of nitrate reductase and thereby inactivates the enzyme

Which of the following statements about regulation of nitrate reductase is correct?