Master Neisseria gonorrhoeae Characteristics with Picmonic for Medicine

Neisseria gonorrhoeae is a gram-negative bacterium, which does not retain crystal violet dye when Gram stained due to thin peptidoglycan layer.

Diplococci are round-shaped bacterium that typically occur in pairs.

Neisseria are fastidious organisms that require nutrient supplementation to grow in laboratory cultures. Specifically, they grow on chocolate agar, which is an enriched growth medium containing red blood cells that have been lysed, providing growth factors like NAD and hemin. The agar is named for the chocolate color of the medium and does not actually contain chocolate.

Thayer-Martin agar is an agar plate containing vancomycin, polymyxin, nystatin, and other nutrients that facilitate the growth of Neisseria species, while inhibiting the growth of other organisms.

Thayer-Martin agar is also called VPN agar and contains vancomycin, polymyxin, nystatin, and other nutrients that facilitate the growth of Neisseria species while inhibiting the growth of other organisms. This is also known as VCN inhibitor, for the combination of antibiotics it has (vancomycin, colistin, and nystatin).

An oxidase test is used to determine if bacteria produce certain cytochrome c oxidases to help differentiate bacteria. Neisseria gonorrhoeae is oxidase-positive.

Neisseria gonorrhoeae can be distinguished from other gram-negative bacteria because the organism is glucose fermenting. However, unlike Neisseria meningitidis, Neisseria gonorrhoeae cannot ferment maltose.

Pili are used to adhere to mucosal surfaces by extending the pili and retracting after attaching to a substrate, causing the organism to drag forward.

Neisseria gonorrhoeae have surface proteins called Opa proteins that bind to receptors on immune cells, and they play a role in preventing an immune response.

Rapid antigenic variation is an important virulence mechanism. Neisseria gonorrhoeae is capable of altering its surface Opa proteins, making it difficult to mount a defense.

An IgA protease is an enzyme that cleaves certain amino acid sequences of proteins including, immunoglobulin A. Neisseria gonorrhoeae releases IgA protease which destroy IgA, leading to increased pathogenicity. Other IgA protease producers include Streptococcus pneumoniae and Haemophilus influenzae type B.