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Proceedings of the 31 st European Peptide SymposiumMichal Lebl, Morten Meldal, Knud J. Jensen, Thomas Hoeg-Jensen (Editors)European Peptide Society, 2010Synthesis of New Polymer Matrices Including Amino AcidsDantcho L. Danalev 1,2 , Jean-Marie Ringeard 1 , Stéphane Serfaty 1 ,Jean-Yves Le Huérou 1 , Emmanuel Caplain 1 , Lyubov K.Yotova 2 ,and Pascal Griesmar 11 Université de Cergy-Pontoise, Cergy-Pontoise, France; 2 University of ChemicalTechnology and Metallurgy, Sofia, Bulgaria, dancho_danalev@yahoo.comIntroductionWater is the main constituent of all living things. Many of them can even live only in thewater. They change the environment by their abstraction and their releases. Finally, lifegrows only at low temperature (below 100 °C). However, in this temperature range, waterand aqueous media are the optimal condition for corrosion of metals. It is therefore naturalthat there is interaction between life and corrosion.Microbiologically induced corrosion (MIC) is a term that is used for a phenomenonwhere corrosion is caused and develops under the influence of microorganisms [1]. Themicroorganisms taking part in this process are mainly bacteria [2,3]. Other organismswhich could induce MIC are fungi that give off acids or algae that form electrochemicalcells [4]. All of this results in MIC. It is considered that 20% of the damages caused bycorrosion are due to MIC [5]. Such damages often occur in the aviation industry and are aserious problem today. The water standing at the bottom of the fuel tank creates a favorableenvironment for the development of microorganisms. They can be aerobic and anaerobic.The aerobic ones tend to produce acid metabolite products which cause corrosion. Theanaerobic microorganisms also cause corrosion as they trigger oxidation-reduction reaction.The most often occurring microorganisms contaminating the fuels are the philamentousfungi Hormoconis resinae, of the genus Cladosporium, Aspergillus, Fusarium, yeast of thegenus Candida, Rhodotrula and bacteria of the genus Pseudomonas, Acinetobacter,Flavobacterium. The listed microorganisms are found in different consortia depending onthe geographic location, composition of the fuels and the temperature. They form biofilmson the surface of the tanks. The revealing of the composition of the formed biofilms andtheir role in the corrosion process could turn out to be an important and promising factor inthe monitoring of this adverse process. By definition, the biofilms (BF) are structurally andfunctionally defined communities of microorganisms on various natural and artificialsurfaces (Figure 1). BF have a complex structure including cells and substances secretedfrom them – mainly exopolymer substances (EPS), and a network of microchannelsthrough which water, nourishing and waste substances circulate.One of the most important factors influencing the formation of BF is the matrix towhich the microorganisms attach. Its influence is affected by the structure of its surface,physicochemical properties, the thickness and the hydrodynamic effects which aredependent on the type of the flow, laminar or turbulent. Another important factor is theliquid environment – composition, ion strength, temperature, pH. Not least important is theinfluence of the properties of the cells and between cells – hydrophobicity of their surface,intrinsic electrical and mechanical interactions, exopolymersubstances, etc.Studies on the biodegradation of morpholine and itsderivatives Poupin et al. found that one of its analoguesthiomorpholine has strong bactericidal properties [6]. Thiscould be used successfully to fight against microbial inducedprocesses by establishing appropriate modified amino acidsand their use as protective layer in the tanks and other metalFig. 1. Polymicrobialbiofilms grown onstainless steel surfaces.deposits. As part of a diet, proteases which normally functionin the bacterial cell would lead to a release of thethiomorpholine, highly toxic to bacteria and their immediatedeath (bactericide properties).70