Neet Solved Paper 2013 Question 39
Question: The colonies of recombinant bacteria appear white in contrast to blue colonies of non-recombinant bacteria because of
Options:
A) Non-recombinant bacteria containing $ \beta\text{ -} $ galactosidase
B) Inspectional inactivation of $ \alpha \text{-} $ galactosidasein non-recombinant bacteria
C) Insertional inactivation of $ \alpha \text{-} $ galactosidase in recombinant bacteria
D) Inactivation of glycosidase enzyme in recombinant bacteria
Show Answer
Answer:
Correct Answer: C
Solution:
- The colonies of recombinant bacteria appear white in contrast to blue calories of non-recombinant bacteria because of insertional inactivation of alpha galactosidase in recombinant bacteria. Alpha galactosidase is a glycoside hydrolase enzyme that hydrolyse the terminal alpha galactosyl moieties from glycolipids and glycoprotein. It is encoded by the GLA gene. $ \beta\text{ -} $ galactosidase is an exoglycosidase, which hydrolyzes the $ \beta\text{ -} $ glycosidic bond formed between a galactose and its organic moiety.
