Govt Exams
Staphylococcus aureus produces coagulase enzyme (plasma coagulation positive), forming clusters and showing variable hemolysis (often alpha or non-hemolytic), distinguishing it from coagulase-negative staphylococci.
Multiple enveloped virus families (orthomyxoviruses, paramyxoviruses, alphaviruses) utilize pH-dependent endosomal fusion for genome release into cytoplasm.
Acinetobacter baumannii forms robust biofilms on environmental surfaces and medical devices, surviving desiccation and disinfection, complicating infection control.
The HN protein of paramyxoviruses mediates both hemagglutination (receptor binding) and neuraminidase activity (sialic acid cleavage), unlike orthomyxoviruses with separate H and N proteins.
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.
Baltimore classification organizes viruses into 7 groups based on replication strategy and genetic material type, applicable to both bacterial and eukaryotic viruses.
Streptococcus pneumoniae is distinguished by optochin sensitivity (alpha-hemolytic) and bile solubility, with lancet-shaped cocci causing bacterial meningitis.
Reverse transcriptase converts retroviral ssRNA into dsDNA, a critical step unique to retroviruses before integration into the host chromosome via integrase.
Mycolic acids in mycobacterial cell walls create a waxy, hydrophobic barrier that retains acid-fast stains and inhibits antimicrobial penetration.