Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology, and Research (A*STAR), 31 Biopolis Way, #04-01, Nanos, Singapore, 138669, Republic of Singapore.
Molecular Engineering Lab, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, #07-06, Proteos, Singapore, 138673, Republic of Singapore.
Microb Cell Fact. 2024 May 24;23(1):149. doi: 10.1186/s12934-024-02416-y.
Streptomyces is renowned for its robust biosynthetic capacity in producing medically relevant natural products. However, the majority of natural products biosynthetic gene clusters (BGCs) either yield low amounts of natural products or remain cryptic under standard laboratory conditions. Various heterologous production hosts have been engineered to address these challenges, and yet the successful activation of BGCs has still been limited. In our search for a valuable addition to the heterologous host panel, we identified the strain Streptomyces sp. A4420, which exhibited rapid initial growth and a high metabolic capacity, prompting further exploration of its potential.
We engineered a polyketide-focused chassis strain based on Streptomyces sp. A4420 (CH strain) by deleting 9 native polyketide BGCs. The resulting metabolically simplified organism exhibited consistent sporulation and growth, surpassing the performance of most existing Streptomyces based chassis strains in standard liquid growth media. Four distinct polyketide BGCs were chosen and expressed in various heterologous hosts, including the Streptomyces sp. A4420 wild-type and CH strains, alongside Streptomyces coelicolor M1152, Streptomyces lividans TK24, Streptomyces albus J1074, and Streptomyces venezuelae NRRL B-65442. Remarkably, only the Streptomyces sp. A4420 CH strain demonstrated the capability to produce all metabolites under every condition outperforming its parental strain and other tested organisms. To enhance visualization and comparison of the tested strains, we developed a matrix-like analysis involving 15 parameters. This comprehensive analysis unequivocally illustrated the significant potential of the new strain to become a popular heterologous host.
Our engineered Streptomyces sp. A4420 CH strain exhibits promising attributes for the heterologous expression of natural products with a focus on polyketides, offering an alternative choice in the arsenal of heterologous production strains. As genomics and cloning strategies progress, establishment of a diverse panel of heterologous production hosts will be crucial for expediting the discovery and production of medically relevant natural products derived from Streptomyces.
链霉菌以其生产具有医学相关性天然产物的强大生物合成能力而闻名。然而，大多数天然产物生物合成基因簇（BGCs）要么产量低，要么在标准实验室条件下保持隐匿状态。已经设计了各种异源生产宿主来解决这些挑战，但 BGCs 的成功激活仍然受到限制。在寻找有价值的异源宿主的过程中，我们发现了一株链霉菌 sp. A4420，它表现出快速的初始生长和高代谢能力，因此进一步探索了其潜力。
我们基于链霉菌 sp. A4420（CH 菌株）设计了一种聚酮化合物为重点的底盘菌株，通过删除 9 个天然聚酮 BGCs。由此产生的代谢简化生物体表现出一致的孢子形成和生长，超过了大多数现有基于链霉菌的底盘菌株在标准液体生长培养基中的性能。选择了四个不同的聚酮 BGCs，并在各种异源宿主中表达，包括链霉菌 sp. A4420 野生型和 CH 菌株，以及变铅青链霉菌 M1152、白色链霉菌 TK24、白色链霉菌 J1074 和委内瑞拉链霉菌 NRRL B-65442。值得注意的是，只有链霉菌 sp. A4420 CH 菌株在每种条件下都能够生产所有代谢产物，表现优于其亲本菌株和其他测试菌株。为了增强测试菌株的可视化和比较，我们开发了一种涉及 15 个参数的矩阵分析。这种综合分析明确说明了新菌株成为一种流行的异源宿主的巨大潜力。
我们构建的链霉菌 sp. A4420 CH 菌株在聚酮类天然产物的异源表达方面表现出有希望的特性，为异源生产菌株提供了另一种选择。随着基因组学和克隆策略的进步，建立一个多样化的异源生产宿主面板对于加速发现和生产源自链霉菌的具有医学相关性的天然产物将至关重要。
