Gram-positive and gram-negative bacteria differ in the composition of their cell walls. Gram-negative bacteria have a double layer of protection, making them more difficult to kill, Muñoz said.

NAB741 is a non-bioactive polymyxin that acts as a Gram-negative antibiotic potentiator, designed to increase the permeability of the outer membrane of Gram-negative bacteria—therefore making those ...

Its discovery in the 1940s generated high hopes for it as a powerful agent against Gram-negative bacteria. But a clinical study found that nourseothricin was toxic to kidneys, so its development ...

First, gram-negative bacteria have a thin cell wall that is about 1.5 to 10 nanometers across, whereas gram-positive bacteria have a thick cell wall measuring about 20 to 80 nanometers.