| Staphylococcus aureus (ScA), one kind of Grans+ bacterium, is a type of common pathogenic coccus that always causes nonspecific infection and nosocomial infection. Some ScA may cause suppurative inflammation of many tissues and organs such as skin, mucous membrane and lung. Others can cause food poisoning, TSS, exofoliation syndrome and etc. Staphylococcus aureus can generate plenty of metabolites including enzyme, toxin and protein A,etc, which are virulence factors and correlate with pathogenicity and tolerance of ScA. Recent studies indicated that these metabolites could cure many human diseases without side effect. For example, Staphylococcus aureus filtrate (SAF) is one kind of new drugs developed according to its therapeutical effect. At first, SAF is used to cure cataclasis. But some time latter, the more effect of this medicine was discovered, for instance, it can prevent edleucocytopenia caused by radiotherapy, and can reinforce people immunity. Now, this medicine is mixture, of which the ingredient is very complicated. So, research on this medicine is very necessary, it is the reason that we change this study as my topic.The work mainly centers about two parts: Part I: Research on one kind of activity polyamines isolated from the SAF.In this part, one kind of activity polyamines was isolated from the SAF. This polyamine has the accelerative effects of the cartilage cell. The isolated steps are as following.Firstly, SAF was separated into big molecular group and small molecular group by sephadex G-25 column. According to some reports, the protein A in the big molecular group has the accelerative effects of the cartilage cell. But cell experiments proved that small molecular group has the accelerative effects of the cartilage cell too. So, we believe that there is some kind of activity polyamine in small molecular group.Secondly, one component was obtained from small molecular group by cation exchange resin column chromatography. After the separation by cation exchange resin column, we gained one kind of polyamines from SAF and analyzed by filter-paper chromatography and further purification.After gaining this polyamine by filter-paper chromatography, we identified what it is through anomi acid analysis, HPLC and IR spectrum. Compared SAF to culture medium by amino acid analysis, the concentration of Arg and Orn has the most obvious change. Results of HPLC proved that the concentration of putrescine and spermine increased obviously.At last, by using the IR spectrum of spermine , spermidine, sample, the pure polyamine is identified spermine. Part II: Research on the coagulase isolated from SAF. In this part, the coagulase in SAF was separated and purified, and its character was researched. The coagulase was obtained by several steps, which were ultra filtrate by using 20kDa film, acetone sediment, etc. Then, it was purified through Sephadex G-200.The purity of coagulase separated by Sephadex G-200 column was analyzed by HPLC, and found its purity is over 97%. Molecular weight of the coagulase was determined by gel filtration on a Sephadex G-200 column calibrated with the molecular weight standards, and the molecular weight of coagulase was 350kDa.The amino acid analysis of the coagulase is analyzed by HPLC and paper chromatography. As the result, the amino acid of the coagulase was found very rich. But in this paper we can see, there is a kind of especial substance in the amino acid analysis chart. Through phenol-vitriol method, result showed that the especial substance is sugar, so the coagulase is a kind of glycoprotein, and the content of sugar in the coagulase is 18.1%.The N-terminal amino acid of the coagulase was identified to be Asp by DNS-Cl method.Circular dichroism (CD) was used to detect its secondary structure with wavelength from 200nm to 300nm and got a positive peak. Comparing it with standard polyLys CD , we could draw a conclusion that the content of α-Helix was 27.3％. At last, we studied the coagulase biology characters.
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