MELITTIN - A REVIEW Vishnu Hemant, Shanti V School of Biosciences and Technology, VIT University, Vellore ABSTRACT Melittin is the prime component of the bee venom. Nearly 40-50% of the bee venom is composed of melittin. . Structurally, it is a small linear peptide and is composed of 26 amino acid residues. Studies have shown its various applications in therapeutics. It basically acts on the cell membrane, disrupts the membrane permeability barrier by a variety of mechanisms leading to the loss of cytoplasmic membrane integrity and eventually cell death. This review paper discusses the membrane interactions of melittin, its antimicrobial properties and various other therapeutic applications of the same. Its activity on cell membrane …show more content…
Chagas disease)[3]. Melittin contains distinct hydrophobic and hydrophilic domains with four cationic amino acids sequestered near the c-terminus. It exhibits a very strong broad spectrum antimicrobial activity and is also highly haemolytic[1,6,7]. Subsequent disruption of the membrane permeability barrier may occur by a variety of mechanisms, leading ultimately to loss of cytoplasmic membrane integrity and cell death. STRUCTURE Structurally, Melittin is a small linear peptide consisting of 26 amino acids. Melittin: G I G A I L K V L A T G L P T L I S W I K N K R K It is of hydrophobic nature. At physiological pH, it has a pH of +6(four at highly basic C- terminal region (Lys-Arg-Lys-Arg) and the remaining two in the N-terminal region, Lys-7 and the N-terminal group (Gly-1)). Melittin happens to be amphipathic due to the asymmetric distribution of the polar and non polar amino acids, when aligned in an alpha- helical configuration[]. Structure showing the Helical wheel projection and schematic representation of the amphipathic helix of melittin the one letter code for amino acids is used. Hydrophobic residues are shown in white, polar residues in gray and cationic residues in black circles. …show more content…
It hinders the production of gag/pol by HIV protease by binding to the gag/pol precursor. [23]. Vaginal cream potential therapeutic application. New research shows that melittin on nanoparticles fuses with the envelope and forms little pore like attack complexes amd ruptures the envelope, stripping it off the virus. MELITTIN FOR TREATMENT OF CHAGAS DISEASE Melittin has shown to be lethal to the Trypanosoma cruzi, the causative agent of chagas disease. It was demonstrated that melittin affected all of the development forms of T.cruzi, including intracellular amastigotes. Epimastigotes were killed by autophagic cell death while trypomastigotes were killed by apoptotic mechanism.[24] CONCLUSION Melittin is one of the most common and naturally occurring antimicrobial peptide. Extensive research has been already done on it so far and much work is still going on the same. Thisone antimicrobial peptide has been shown to have potential for so much therapeutic applicatons such as antimicrobial and antiviral uses, colonal cancer,etc. Much more biophysical studies have to be done for further understanding its cellular and membranal activities and
In vitro: Treatment of MM cells with SRT1720 inhibited growth and induced apoptosis in MM cells resistant to bortezomib therapy without significantly affecting the viability of normal cells. Mechanistic studies demonstrated that anti-MM activity of SRT1720 is associated with activation of caspase-3, caspase-8, caspase-9, poly(ADP) ribose
1. Identify all the options. James Sullivan and his partner Melin, had the option of giving a true statement about Francis case to U.S District court in Brooklyn. 2. Identify all those affected by the decision.
The author starts by explaining the human microbiome and the research on it. For many years, biologists thought that the human body was able to perform all of its important functions by itself. However, in the past decade, they have found that the human body contains trillions of microorganisms that help with these important processes. In fact, they outnumber human cell 10 to one. At first, microbe research was only focused on harmful pathogens, but recently, biologists have figured out what the most common bacteria in the human body are, and have been trying to figure out the specific functions of theses microorganisms.
ABSTRACT NRC-04, a novel antimicrobial peptide derived from skin mucous secretions of flat fish winter flounder, shows a broad spectrum of antimicrobial activity. In order to understand the conformational change of NRC-04 in different types of membrane, our team did experiments on NRC-04 with negatively charged bacterial surface membrane mimetic micelles sodium dodecyl sulphate(SDS), zwitterionic eukaryotic middle membrane mimetic micelles dodecylphosphocholine(DPC), gram-negative bacteria outer membrane mimetic micelles Lipopolysaccharide(LPS) and bacterial inner membrane mimetic micelles 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol(POPG). Fluorescence test shows that the C-terminus tryptophan residue of NRC-04 interacts with the hydrophobic
Inflammation is the main type of innate immunity our body uses against A. schmiddy. Inflammation begins by activating acute-phase proteins, and soon after vasodilation occurs, followed by redness, swelling, pain, and heat. Once vasodilation occurs, histamine and kinins are released and blood vessels permeability is increased, causing white blood cells to report to the infected area. One problem associated with inflammation is that the capsule of A. schmiddy is an important virulence factor, which helps the bacteria to resists phagocytosis. Because the phagocytes cannot destroy the bacteria cells, infection further continues and necrotic tissue forms.
The lipid A has phosphoethanolamine added to it, which in turn, inhibits the bacteria from any attachment. Q3E: What is the origin of the mcr-1 gene, and what evidence do the authors use to support this
The peptide when further engineered makes two slightly different versions i.e. Melanotan 1 and 2. The two types mimic the body’s alpha-melanocyte and a stimulating hormone known (α-MSH) produced in the pituitary gland. Working like other body melanocortins, they are main agents that cause a number of internal body functions to happen such as hair and skin pigmentation, appetite changes, and raising your libido level. Both the sexual function and libido level changes are only exclusive to Melanotan
The bacterium is resistant to many antibiotic therapies, which makes
After that, a spin vane was inserted into the vial while adding 0.75 mL of 1M H2SO4 solution. During the addition of the sulphuric acid, the solution was stirred at room temperature until the amino acid (L-Phe) completely dissolved. An ice bath was prepared and used for cooling the L-Phenylalanine solution at a temperature of 40C (a selected temperature lower than 50C). Once the solution was cooled, the first portion
However, all proteins are constructed from the same set of 20 amino acids linked in unbranched polymers. The covalent bond that exists between amino acids is called peptide bond, hence a polymer of amino acids is named polypeptide. A protein is a biological functional molecule made up of one or more polypeptides which is folded and coiled into unique three-dimensional structure. In laboratory, it is important to measure the concentration of proteins for research investigations. Biuret test is adopted to quantify proteins in fluid by using a spectrophotometer.
This is launched to enhance the understanding of the role of Microbiome in the ecology of humans and using the concerned knowledge in the development of therapies for various illnesses (About MGH, nd, News Releases). The department of chemistry and biological engineering, and MIT institute of medical engineering and science are involved in collaboration with MGH clinical medicine. This new partnership will follow the one that was implemented among MIT, Ragon Institute of MGH and Harvard, which started in 2009 and worked on developing effective vaccine against AIDS as a part of their study on the role of immune system in human disease (MIT News, Oct. 15, 2014). This new partnership between MIT and MGH has offered $3 million to a two-year period research project dealing with the problems in diagnostics, autoimmune and infectious diseases and in
In part 2, using the Michaelis-Menten kinetics of the enzyme, identified the inhibitor (75 mM phenylalanine) as an uncompetitive inhibitor. This is because Vmax and Km decrease when the inhibitor is added (7). The function of reversible, uncompetitive inhibitors is the removal of the enzyme substrate complex from circulation. This is done by the reaction creating an enzyme-substrate-inhibitor complex. An example of a common drug that is a noncompetitive inhibitor is the herbicide, Roundup.
Six functions of membrane proteins are transport, enzymatic activity, signal transduction, cell-cell recognition, intercellular joining and attachment to the cytoskeleton and extracellular matrix (ECM). Some membrane proteins span the membrane to provide a hydrophilic channel for hydrophilic substances to be able to pass through the lipid bilayer while other transport proteins are able to change their shapes to help move specific substances from one side to the other; some proteins use ATP as an energy source to actively move substances from one side of the membrane to the other. Some proteins are enzymes that are built into the membrane, with the enzyme’s active site open for substances to enter and act as a “team” to help carry out necessary
(Tanta City, Cairo, Egypt). Animals were housed in a room free from any source of chemical contamination, artificially illuminated and thermally controlled at the Animal House Lab., Pharmacology and Chemistry Research Centre, Misr University for Science and Technology (6th October, Giza, Egypt). After an acclimatization period of 1 week, the animals were divided into four groups (10 rats/group) and housed in filter-top polycarbonate cages (five rats per cage). All animals have received human care in compliance with the guidelines of the Animal Care and Use Committee of the Pharmacology and Chemistry Research Centre (6th October City, Giza, Egypt). Infection Model Circular Excision Wound Model For the evaluation of the antibacterial activity, each rat was undergo anaesthesia by intraperitoneal injection of a combination of 10% ketamine hydrochloride (50 mg/kg) and 2% xylazine hydrochloride (5 mg/kg).
Its virulence factor comes from multiple things within the cell and these things contribute to the types of infections they cause. Two important virulence factors are a secreted protein called coagulase and clumping factor. Some other virulent factors are the capsule, enterotoxins, exfoliatin, toxic shock syndrome toxin, and alpha toxin. The enterotoxins cause food poisoning in humans. The exfoliatin caused scalded skin syndrome.