sentence: Interestingly , the newly generated peptides NP1P , NP2P , and NP3P showed marked increased in antibacterial activity against the gram-positive Staphylococcus aureus , Bacillus subtilis , and Micrococcus luteus as well as the gram-negative Pseudomonas aeruginosa , Salmonella typhimurium , Escherichiae coli , and Serratia marcescens13 .