The insect ingests plant tissue containing the fatty acids, an enzyme in the gut conjugates the plant-derived fatty acid to an insect-derived amino acid to form an elicitor, When plants recognize elicitors from insect saliva induces some typical responses such as

a) Increasing Ca²⁺ levels in the cytosol and then activate an array of target proteins, such as calmodulin and other Ca²⁺-dependent protein kinases

b) In Arabidopsis, a calmodulin-binding transcriptional regulator called IQD1 was identified as an important mediator of defense responses against insect herbivory

c) overexpression of IQD1 in Arabidopsis activate the herbivore activity

d) IQD1 binds calmodulin, a major Ca2+-binding protein, in a Ca2+-dependent manner and subsequently inhibits the gene involved in glucosinolate biosynthesis

Which of the following combination from above statements is correct?

#Question id: 1639

#SCPH01 Biochemistry

T-cell surface receptors for antigen partly recognize:

#Question id: 568

#SCPH05 I Biotechnology

Which of the following statements about allosteric control of enzymatic activity is false?

#Question id: 14156

#SCPH01 Biochemistry

#Question id: 643

#SCPH05 I Biotechnology

The hydrolysis of lactose is catalysed by b-galactosidase as given below

Which of the following could be correct mechanism for this hydrolysis reaction?

A. Nucleophilic attack by the carboxylate group of Glu/Asp on the C-1 carbon atom of the galactose moiety within glucose, releasing glucose and forming an intermediate with the galactose linked to the enzyme through an ester linkage. Water then attacks this carbon atom, displacing the glutamate carboxylate and releasing galactose.

B. Electrophilic attack by the carboxylate group of Glu/Asp on the C-1 carbon atom of the galactose moiety within glucose, releasing glucose and forming an intermediate with the galactose linked to the enzyme through an ester linkage. Water then attacks this carbon atom, displacing the glutamate carboxylate and releasing galactose.

C. Nucleophilic attack by the carboxylate group of Lys/Arg/His or bivalent cation on the C-1 carbon atom of the galactose moiety within glucose, releasing glucose and forming an intermediate with the galactose linked to the enzyme through an ester linkage. Water then attacks this carbon atom, displacing the glutamate carboxylate and releasing galactose.

#Question id: 18682

#SCPH01 Biochemistry