Suwanpatcharakul Maethichai, Pakdeecharoen Chompunut, Visuttitewin Supitcha, Pesirikan Norapath, Chauvatcharin Somchai, Pongtharangkul Thunyarat
Department of Biological Products, The Government Pharmaceutical Organization (GPO), Bangkok, Thailand.
Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok, Thailand.
Biologicals. 2016 Nov;44(6):534-539. doi: 10.1016/j.biologicals.2016.08.002. Epub 2016 Sep 15.
In this study, several parameters affecting the toxin production of Corynebacterium diphtheriae Parke Williams 8 (PW8) were investigated in detail. The comparison studies of amino acid profile in NZ Amine A-based medium (NZ medium) and beef digest-based medium (BD medium) suggested that an insufficient supply of amino acids was not responsible for low toxin yield observed in NZ medium. Supplementation of additional amino acids and growth promoting nutrient (in a form of yeast extract) into NZ medium enhanced only cell growth but not toxin production. Thus, BD medium was selected as the most suitable base medium for toxin production as it gave a significantly higher limit of flocculation (93 ± 0 Lf/ml) than NZ medium (46 ± 0 Lf/ml). Interestingly, a supplementation of 0.2% YE into BD medium resulted in a significant increase in growth as well as toxin production (235 ± 5 Lf/ml). In conclusion, consistently high toxin titer (174-239 Lf/ml) could be obtained from BD medium at a 5 L-scale production as long as 1) the protein content of BD medium was at least 24 g/L, 2) the iron content was below 0.15 ppm and 3) 0.2% YE was supplemented into the medium.
在本研究中，详细调查了影响白喉棒状杆菌帕克·威廉姆斯8型（PW8）毒素产生的几个参数。基于NZ胺A的培养基（NZ培养基）和基于牛肉消化物的培养基（BD培养基）中氨基酸谱的比较研究表明，氨基酸供应不足并非NZ培养基中毒素产量低的原因。向NZ培养基中添加额外的氨基酸和生长促进营养物质（酵母提取物形式）仅增强了细胞生长，而非毒素产生。因此，BD培养基被选为最适合毒素产生的基础培养基，因为它的絮凝极限（93±0 Lf/ml）明显高于NZ培养基（46±0 Lf/ml）。有趣的是，向BD培养基中添加0.2%的YE导致生长以及毒素产生显著增加（235±5 Lf/ml）。总之，只要1）BD培养基的蛋白质含量至少为24 g/L，2）铁含量低于0.15 ppm，3）向培养基中添加0.2%的YE，在5 L规模生产中就可以从BD培养基中持续获得高毒素滴度（174 - 239 Lf/ml）。
