Exploring The Binding Affinity Of Several Cephalosporins And Biomacromolecules

As the bacteria inhibitor,antibiotics have been widely used in clinical therapy and animal breeding.The emission effluent which is contained with substantial expired antibiotics,waste antibiotics and animal excrements destroy the stable ecological environment.The major characteristic of cephalosporin is to restrain bacterial infection,which mostly caused by majority gram negative(–)and gram positive(+)bacterias.The total production,application amount,and the type of cephalosporin are located in superior level than other antibiotics.The molecular structural of cephalosporins display diversity and variety.The heavy metal ions were distributed into environment,which originating from industrial manufacture through by water,soil and atmosphere.Some heavy metal ions having strong genetic toxicity,and non-biological activity.They can?t be removed by metabolism.For long time,these metal ions were accumulated in organs,undoubtedly,these accumulation ions were harmful for health.This paper using biological methods to analyze the affinity of cephalosporins with biomacromolecules in unique structural view.The different side chain of 3 and 7 position of 7-aminocephalosporanic acid of cephalosporin were investigated.The additional heavy metal ions have strong genetic toxicity and the interaction of ternary systems(cephalosporins-biomacromolecules-heavy metal ions)was also explored.This dissertation is split into five chapters,and the main contents should be summarized as follows:Chapter one: This chapter introduces the production,application,emission,and pollution status of antibiotics or heavy metal ions,which are two kinds of mainly environmental pollutants.The research methods or status for the interaction between small molecules and biomacromolecules were summarized.In additional,the research meaning and characteristics were expatiated.Chapter two: The affinity of antibiotics to DNA were explored by choosing cefaclor(the second generation cephalosporin)and cefixime(the third generation cephalosporin).The UV-vis,fluorescence spectra approaches,molecular simulation technology and electrochemical method were used to monitor the interactional mechanisms.The information of molecular structural on binding process was analysed.This chapter also exploration several influencing factors such as temperature,ionic strength,denaturant,thermal denaturation,heating time and heavy metal ions.Chapter three: Using UV-vis,fluorescence spectrum approach,and molecular simulation technology to explore the interaction of cephalosporins(cefalexin and cefixime)with bovine serum albumin.The structural differences between cefalexin and cefixime was analysed;the relevant inter-function mechanism of antibiotics with bovine serum albumin were inquired;the inter-binding sites,changing-shift of micro-environment which is around with the amino acid residues,and inter-binding information since the addition of heaven metal ions were also explored.Chapter four: UV-vis spectrometry,fluorescence spectrometry,circular dichroism spectrometry,electrochemical method and molecular simulation technology were chosen to investigate the interaction of several cephalosporins(cefalexin,cefaclor,cefixime and cefepime)with human serum albumin.The molecular structural differences of four kind of cephalosporins was compared in our study.The interactional relevant mechanism,the mainly inter-force,and the inter-binding sites of antibiotics to human serum albumin also analysed.Synchronous fluorescence,3D-fluorescence,and circular dichroism spectrometry were used to investigate the conformational change for human serum albumin.In our study,the inter-electron transfer information and the detail binding information also summarized.Chapter five: Summarized the whole paper and put forward some subsequent growth in this field.