The stages in the formation of the symbiotic relationship between the nitrogen-fixing bacteria and their host, Arrange the given statements of symbiotic association in a stepwise manner;

 a) Migration of the bacteria toward the roots of the host plant by a chemotactic response mediated by chemical attractants

b) NodD with the flavonoids bind with the Promoter region of  highly conserved the nod box

c) These attractants activate the rhizobial NodD protein,

d) The chemical attractants especially (iso)flavonoids and betaines, secreted by the roots

e) Binding of the activated NodD to the nod box induces transcription of the other nod genes

 Which of the following from the above statements are correct arrangement of symbiosis?

#Question id: 629

#Unit 1. Molecules and their Interaction Relevant to Biology

In the presence of a fixed concentration of a competitive inhibitor, which of the following would best characterize an enzyme-catalyzed reaction when the concentration of the substrate is increased?

#Question id: 630

#Unit 1. Molecules and their Interaction Relevant to Biology

In case of competitive inhibition, plots of Km against [Io] fixed [Eo] have

#Question id: 631

#Unit 1. Molecules and their Interaction Relevant to Biology

Two curves showing the rate versus substrate concentration are shown below for an enzyme-catalyzed reaction. One curve is for the reaction in the presence of substance X. The other curve is for data in the absence of substance X. Examine the curves and tell which statement below is false.

#Question id: 633

#Unit 1. Molecules and their Interaction Relevant to Biology

An amino acid transporter protein is responsible for the transport of a specific amino acid across a membrane. The KI values of several competitive inhibitors of the amino acid transporter are shown above. Based on these data, which of the following is most likely the amino acid transported by this protein?

#Question id: 634

#Unit 1. Molecules and their Interaction Relevant to Biology

An enzyme has a Vmax of 50 micromol product formed (minute x mg protein)-1 and a Km of 10 microM for the substrate. When a reaction mixture contains the enzyme and 5 microM substrate, which of the following percentages of the maximum velocity will be closest to the initial reaction rate?

#Question id: 635

#Unit 1. Molecules and their Interaction Relevant to Biology

The enymatic rate constant (kcat/Km) of orotidine 5ʹ-phosphate decarboxylase is 6 x 10⁷ M^-1s^-1 and the nonenzymatic rate constant (kn) is 3 x 10^-16 s^-1.  What is the value of the enzymeʹs catalytic proficiency?