Govt. Exams
Entrance Exams
Integrase catalyzes the insertion of viral DNA into the host chromosome, establishing persistent infection in retroviruses like HIV.
HSV establishes latency in dorsal root ganglia and trigeminal ganglia, leading to recurrent herpes infections.
Diphtheria toxin catalyzes ADP-ribosylation of EF-2, blocking translation and causing severe systemic toxicity.
Mycobacterium tuberculosis has a waxy cell wall rich in mycolic acids that require acid-fast staining for visualization.
The F pilus establishes a bridge between donor and recipient cells for plasmid transfer during bacterial conjugation.
Retroviruses like HIV use reverse transcriptase to synthesize DNA from their RNA genome for integration into host DNA.
Mycoplasma lacks a cell wall and does not stain with Gram staining but is detectable by PCR, causing atypical pneumonia.
The spike protein of SARS-CoV-2 has high affinity for ACE2 receptors, enabling efficient cellular entry and transmission.
R plasmids carrying antibiotic resistance genes are readily transferred via conjugation across species barriers, explaining rapid resistance dissemination in clinical settings.
Vibrio vulnificus is a salt-tolerant marine bacterium causing wound infections through contaminated seawater exposure, particularly in immunocompromised individuals.