Ozcengiz G, Alaeddinoglu N G, Demain A L
Biology Department, Middle East Technical University, Ankara, Turkey.
J Ind Microbiol. 1990 Oct;6(2):91-100. doi: 10.1007/BF01576428.
Production of the dipeptide antibiotic bacilysin by Bacillus subtilis 168 was growth associated and showed no evidence of repression by glucose or sucrose. Carbohydrates other than glucose and sucrose yielded lower specific titers of bacilysin. Bacilysin production in three such carbon sources (maltose, xylose, ribose) was delayed until growth slowed down. Ammonium salts were poor for bacilysin production when used as the sole nitrogen source. When added to the standard medium containing glutamate, they suppressed antibiotic production. Aspartate was slightly better than glutamate for antibiotic production as sole nitrogen source. No other nitrogen source tested, including inorganic, organic or complex, approached the activity of glutamate or aspartate. When added to glutamate, casamino acids, phenylalanine and alanine (a substrate of bacilysin synthetase) suppressed bacilysin production while stimulating growth. Phosphate provided for optimum growth and production at 7.5 mM and both processes were inhibited at higher concentrations. Ferric citrate stimulated growth and inhibited bacilysin production, the effects being due to both the iron and the citrate components. Elimination of ferric citrate stimulated production as did increasing the concentration of Mn to its optimum concentration of 6.6 x 10(-4) M.
枯草芽孢杆菌168产生二肽抗生素杆菌溶素与生长相关，且未显示出受葡萄糖或蔗糖抑制的迹象。除葡萄糖和蔗糖外的碳水化合物产生的杆菌溶素比滴度较低。在三种此类碳源（麦芽糖、木糖、核糖）中，杆菌溶素的产生会延迟至生长放缓。当用作唯一氮源时，铵盐不利于杆菌溶素的产生。当添加到含有谷氨酸的标准培养基中时，它们会抑制抗生素的产生。天冬氨酸作为唯一氮源时，其抗生素产生能力略优于谷氨酸。所测试的其他氮源，包括无机、有机或复合氮源，均未达到谷氨酸或天冬氨酸的活性。当添加到谷氨酸中时，酪蛋白氨基酸、苯丙氨酸和丙氨酸（杆菌溶素合成酶的一种底物）会抑制杆菌溶素的产生，同时刺激生长。磷酸盐在7.5 mM时可实现最佳生长和产生，在较高浓度下这两个过程均受到抑制。柠檬酸铁刺激生长并抑制杆菌溶素的产生，其作用归因于铁和柠檬酸盐成分。去除柠檬酸铁会刺激产生，将锰的浓度增加到其最佳浓度6.6×10⁻⁴ M也会如此。
