迫切需要生物可降解塑料来替代石油衍生的聚合物材料并防止它们在环境中的积累。为此,我们从犹他州的大盐湖中分离并鉴定了嗜盐和嗜碱细菌。该分离物被鉴定为Halomonas物种,并命名为“CUBES01”。“全基因组测序和基因组重建揭示了菌株独特的遗传性状和代谢能力,包括常见的聚羟基链烷酸(PHA)生物合成途径。荧光染色鉴定细胞内聚酯颗粒主要在菌株的指数生长过程中积累,在天然PHA生产者中很少发现的特征。CUBES01被发现代谢一系列可再生碳原料,包括葡糖胺和乙酰葡糖胺,以及蔗糖,葡萄糖,果糖,和进一步的甘油,丙酸盐,和醋酸盐。根据基材的不同,该菌株在聚(3-羟基丁酸酯)中积累了高达其生物量的〜60%(干wt/wt),在30°C时达到1.7h的倍增时间,最佳渗透压为1M氯化钠,pH为8.8。菌株的生理偏好不仅可以实现长期无菌培养,而且还可以促进通过渗透分解释放细胞内产物。基本培养基的开发还允许估计最大聚羟基丁酸酯的生产率,预计超过5g/h。最后,还,在接合实验中评估了该菌株的遗传可操作性:两个正交质粒载体在异源宿主中稳定,从而通过引入外源基因打开了基因工程的可能性。
目的:对合成材料的可再生替代品的迫切需求可以通过微生物生物技术来解决。为了简化这种生物过程的大规模实施,能够利用可持续和广泛可用的原料的强大的细胞工厂至关重要。为此,非无菌生长相关生产可以降低运营成本并提高生物量生产率,从而提高商业竞争力。另一个主要的成本因素是下游加工,特别是在细胞内产物的情况下,如生物聚酯。简化的细胞裂解策略还可以进一步提高经济可行性。
Biodegradable plastics are urgently needed to replace petroleum-derived polymeric materials and prevent their accumulation in the environment. To this end, we isolated and characterized a halophilic and alkaliphilic bacterium from the Great Salt Lake in Utah. The isolate was identified as a Halomonas species and designated \"CUBES01.\" Full-genome sequencing and genomic reconstruction revealed the unique genetic traits and metabolic capabilities of the strain, including the common polyhydroxyalkanoate (PHA) biosynthesis pathway. Fluorescence staining identified intracellular polyester granules that accumulated predominantly during the strain\'s exponential growth, a feature rarely found among natural PHA producers. CUBES01 was found to metabolize a range of renewable carbon feedstocks, including glucosamine and acetyl-glucosamine, as well as sucrose, glucose, fructose, and further glycerol, propionate, and acetate. Depending on the substrate, the strain accumulated up to ~60% of its biomass (dry wt/wt) in poly(3-hydroxybutyrate), while reaching a doubling time of 1.7 h at 30°C and an optimum osmolarity of 1 M sodium chloride and a pH of 8.8. The physiological preferences of the strain may not only enable long-term aseptic cultivation but also facilitate the release of intracellular products through osmolysis. The development of a minimal medium also allowed the estimation of maximum polyhydroxybutyrate production rates, which were projected to exceed 5 g/h. Finally, also, the genetic tractability of the strain was assessed in conjugation experiments: two orthogonal plasmid vectors were stable in the heterologous host, thereby opening the possibility of genetic engineering through the introduction of foreign genes.
OBJECTIVE: The urgent need for renewable replacements for synthetic materials may be addressed through microbial biotechnology. To simplify the large-scale implementation of such bio-processes, robust cell factories that can utilize sustainable and widely available feedstocks are pivotal. To this end, non-axenic growth-associated production could reduce operational costs and enhance biomass productivity, thereby improving commercial competitiveness. Another major cost factor is downstream processing, especially in the case of intracellular products, such as bio-polyesters. Simplified cell-lysis strategies could also further improve economic viability.