If the peptidoglycan layer is thin, it's classified as gram negative. A gram-positive bacillus doesn't have an outer cell wall beyond the peptidoglycan membrane. This makes it more absorbent.

Abstract and Introduction Empirical Antimicrobial Therapy Against Gram-negative Pathogens Adverse Consequences Related to Combination Antimicrobial Use Conclusion References A recent retrospective ...

Scientists led by Karla Satchell, Ph.D., the Anne Stewart Youmans Professor of Microbiology at Northwestern University, have ...

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.

Researchers at the University of Oklahoma have made a discovery that could potentially revolutionize treatments for antibiotic-resistant infections, cancer and other challenging gram-negative ...