Abstract The Invention relates to novel cationic peptides with Antimicrobial activity and low hemolytic activity and antiparasitic.Also included are analogues, derivatives and Variations of the same Conservative.The peptides are characterized by the sequence of 17 l - amino acids selected from the group consisting nvaax1ax2x3x4lkk x5x6kki,Where: x1 (T), threonine or tryptophan (W) x2 is Arginine (R) or lysine (k), X3 is Glycine (g), phenylalanine (f).Or (and) tyrosine, tryptophan (W) is X4 or X5 is phenylalanine (f), isoleucine (i), (k) lysine or tryptophan (W), and X6 is Glycine (g) or phenylalanine (f).The peptides obtained exhibited Antimicrobial activity against Gram positive and Gram negative such as methicillin resistant Staphylococcus aureus (MRSA),Escherichia coli O157: H7 and Pseudomonas aeruginosa. In addition, exhibits antiparasitic activity against Leishmania Leishmania donovani and pifanoi.RESUMEN La invención se refiere a nuevos péptidos catiónicos con actividad antimicrobiana y antiparasitaria y baja actividad hemolítica. También se incluyen análogos, derivados y variaciones conservativas de los mismos. Los péptidos se caracterizan por la secuencia de 17 L-aminoácidos seleccionada del grupo que consiste en NVAAX1AX2X3X4LKK X5X6KKI, en donde: X1 es Treonina (T) o Triptófano (W) X2 es Arginina (R) o Lisina (K), X3 es Glicina (G), Fenilalanina (F).o Tirosina (Y), X4 es Triptófano (W) o Fenilalanina (F), X5 es Isoleucina (I), Lisina (K) o Triptófano (W), y X6 es Glicina (G) o Fenilalanina (F). Los péptidos obtenidos exhiben actividad antimicrobiana frente a bacterias Gram-positivas y Gram-negativas tales como Staphylococcus aureus Resistente a Meticilina (SARM), Escherichia coli O157:H7 y Pseudomonas aeruginosa. Además, exhibe actividad antiparasitaria frente al parasito Leishmania donovani y Leishmania pifanoi.
