Department of Biology, College of Science, University of Jeddah, Jeddah, Saudi Arabia.
Faculty of Pharmacy, Cairo University, kasr El-Aini, Cairo, 11562, Egypt.
J Appl Genet. 2021 Feb;62(1):165-182. doi: 10.1007/s13353-020-00597-x. Epub 2021 Jan 7.
Genetic manipulation of the undecylprodigiosin-producing strains and engineered culture medium approaches were applied as the most economical induction strategy for improving production. The hyper-producing recombinant strain ALAA-R20 was obtained after applying protoplast fusion strategy between the potent producer marine endophytic strains Streptomyces sp. ESRAA-10 (P1) and Streptomyces sp. ESRAA-31 (P2) of Dendronephthya hemprichi. Recombinant strain ALAA-R20 produced undecylprodigiosin yield higher than its parental strains ESRAA-10 and ESRAA-31 by 82.45% and 105.52% under submerged fermentation using modified R2YE medium. In order to reduce the costs of producing undecylprodigiosin, a solid-state fermentation (SSF) was applied. Scaled-up of optimized SSF parameters consisting of groundnut oil cake (GOC) sized to 3 mm, initial moisture content 80% with a mixture of dairy mill and fruit processing wastewaters (1:1), pH 7.0, inoculum size equal to 3 × 10 spores/g dry substrate (gds), incubation temperature 30 °C, and 7-day incubation period yielded the highest yield of 181.78 mg/gds of undecylprodigiosin by the recombinant strain Streptomyces sp. ALAA-R20. Extraction and purification of the pigment using the chromatographic techniques as well as mass spectral analysis exhibited maximum absorbance at 539 nm which is physiological property of the undecylprodigiosin. Undecylprodigiosin was stable over a wide temperature ranged from - 20 to 35 °C even after storage for 6 months. The maximum yield and stability of pigment was obtained at the acidic pH (acidified methanol, pH 4.0). Undecylprodigiosin obtained from the recombinant strain Streptomyces sp. ALAA-R20 demonstrated strong antimicrobial activity against all multidrug-resistant bacterial and fungal strains tested with minimum inhibitory, minimum bactericidal, and minimum fungicidal concentrations ranged between 0.5 and 4.0, 0.5 to 4.0, and 1.0 to 8.0 μg/mL, respectively. It also showed complete inhibition of cancer cells; HCT-116, HepG-2, MCF-7 and A-549 at 5, 8, 4, and 7 μM with IC equal to 2.0, 4.7, 1.2, and 2.8 μM, respectively.
采用遗传操作和工程化培养基方法，作为提高产量的最经济诱导策略。通过对采自软珊瑚内生真菌链霉菌属（ESRAA-10）（P1）和链霉菌属（ESRAA-31）（P2）的有效生产菌株进行原生质体融合策略，获得了高产重组菌株 ALAA-R20。在改良的 R2YE 培养基中进行深层发酵，重组菌株 ALAA-R20 的产量比其亲本菌株 ESRAA-10 和 ESRAA-31 分别提高了 82.45%和 105.52%。为了降低生产成本，采用固态发酵（SSF）。通过优化 SSF 参数，包括将花生饼（GOC）尺寸缩小到 3mm，初始含水量为 80%，并用乳制品厂和水果加工厂废水（1:1）混合，pH 值为 7.0，接种量等于 3×10孢子/g 干基质（gds），培养温度为 30°C，培养 7 天，重组菌株 Streptomyces sp.ALAA-R20 的产量最高，达到 181.78mg/gds。采用色谱技术和质谱分析提取和纯化色素，显示最大吸收波长为 539nm，这是十一碳烯基深红菌素的生理特性。十一碳烯基深红菌素在-20 至 35°C 的宽温度范围内稳定，即使储存 6 个月后也是如此。在酸性 pH 值（酸化甲醇，pH4.0）下，色素的最大产量和稳定性最高。从重组菌株 Streptomyces sp.ALAA-R20 中获得的十一碳烯基深红菌素对所有测试的多药耐药细菌和真菌菌株均表现出较强的抗菌活性，最小抑菌、最小杀菌和最小抑菌浓度范围分别为 0.5 至 4.0μg/mL、0.5 至 4.0μg/mL 和 1.0 至 8.0μg/mL。它还对癌细胞 HCT-116、HepG-2、MCF-7 和 A-549 表现出完全抑制作用，IC 分别为 5、8、4 和 7μM，IC 为 2.0、4.7、1.2 和 2.8μM。
