Is Pseudomonas classified as gram-positive or gram-negative?

Pseudomonas is classified as gram-negative bacteria because it possesses a thin peptidoglycan layer and an outer membrane that contains lipopolysaccharides. This structure is characteristic of gram-negative organisms, which do not retain the crystal violet stain used in the Gram staining procedure, instead appearing pink after being counterstained with safranin. The classification of Pseudomonas as gram-negative is significant for understanding its biology, pathogenicity, and treatment options, as gram-negative bacteria often exhibit resistance to antibiotics due to their cell wall structure. Therefore, recognizing Pseudomonas as gram-negative is crucial in fields such as microbiology and infectious disease management.