%0 Journal Article %T Antimicrobial Lactoferrin Peptides: The Hidden Players in the Protective Function of a Multifunctional Protein %A Mau Sinha %A Sanket Kaushik %A Punit Kaur %A Sujata Sharma %A Tej P. Singh %J International Journal of Peptides %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/390230 %X Lactoferrin is a multifunctional, iron-binding glycoprotein which displays a wide array of modes of action to execute its primary antimicrobial function. It contains various antimicrobial peptides which are released upon its hydrolysis by proteases. These peptides display a similarity with the antimicrobial cationic peptides found in nature. In the current scenario of increasing resistance to antibiotics, there is a need for the discovery of novel antimicrobial drugs. In this context, the structural and functional perspectives on some of the antimicrobial peptides found in N-lobe of lactoferrin have been reviewed. This paper provides the comparison of lactoferrin peptides with other antimicrobial peptides found in nature as well as interspecies comparison of the structural properties of these peptides within the native lactoferrin. 1. Introduction The innate immune system or the nonspecific immune system is the first and the oldest line of defense in organisms [1, 2]. It was the most dominant form of immunity before the evolution of the more sophisticated adaptive immunity. It is comprised of various mechanisms which are responsible for rapid defense of the host organism against invasion by other factors in a nonspecific manner. The innate immune system differs from the adaptive immune system in a way that while it is able to defend the body against pathogens, it is not able to impart long-lasting immunity to the host, unlike the latter [3]. Despite the evolution of the more complex and specific adaptive immunity, innate immunity still continues to function as the primary line of defense for most organisms [4]. The antimicrobial action in the innate immunity is mediated by various antimicrobial proteins and peptides, which have been evolutionary conserved. Antimicrobial peptides are small peptides which demonstrate broad-spectrum antibiotic activity against various gram-positive and gram-negative bacteria, fungi, protozoa, and viruses [5每8]. While the most common mechanism of action deployed by these peptides is perturbation of microbial cell membrane [9每11], there are other mechanisms which are also prevalent [12每16]. Due to increasing resistance to antibiotics, there is an urgent requirement of novel antimicrobial drugs [17每19]. Use of antimicrobial peptides is one of the promising approaches which may lead to potential antimicrobial drugs [16, 20每24]. It has been observed that peptides which are predominantly cationic and hydrophobic in nature show potent antimicrobial activity [5, 25每29]. Many of these peptides including indolicidin from bovine %U http://www.hindawi.com/journals/ijpep/2013/390230/