gramnegatívnej
Gramnegatívnej refers to a characteristic of bacteria that do not retain the crystal violet stain during Gram staining procedures. Instead, they are counterstained by safranin, appearing pink or red under a microscope. This staining property is due to differences in the cell wall structure of these bacteria. Gram-negative bacteria have a thinner peptidoglycan layer compared to Gram-positive bacteria and an outer membrane containing lipopolysaccharides. This outer membrane provides an additional barrier that the crystal violet stain cannot easily penetrate. The presence of this outer membrane also contributes to the resistance of Gram-negative bacteria to certain antibiotics and disinfectants. Many pathogenic bacteria, such as Escherichia coli, Salmonella, and Pseudomonas aeruginosa, are Gram-negative. Understanding the Gram stain classification is crucial in microbiology for identifying and classifying bacteria, as well as for guiding treatment strategies for infections. The distinction between Gram-positive and Gram-negative bacteria is a fundamental concept in bacterial taxonomy and diagnostics.