Journal of Industrial Microbiology & Biotechnology

Narrow spectrum antibiotics are of great interest given their ability to spare the microbiome and decrease widespread antibiotic resistance compared to broad spectrum antibiotics. Herein we screened an in-house library of Actinobacteria strains for selective activity against Acinetobacter baumannii and successfully identified Streptomyces sp. CS-62 as a producer of a natural product with this valuable activity. Analysis of the cultures via high resolution mass spectrometry and tandem mass spectrometry followed by comparison with molecules in the Natural Product Atlas (NP Atlas) and the Global Natural Products Social Molecular Networking (GNPS) platform suggested a novel natural product...

The mutant strain H. bluephagenesis (TDH4A1B5P) was found to produce PHA under low-salt, non-sterile conditions, but the yield was low. To improve the yield, different nitrogen sources were tested. It was discovered that urea was the most effective nitrogen source for promoting growth during the stable stage, while ammonium sulfate was used during the logarithmic stage. The growth time of H. bluephagenesis (TDH4A1B5P) and its PHA content were significantly prolonged by the presence of sulfate ions. After 64 hours in a 5-liter bioreactor supplemented with sulfate ions, the dry cell weight of H...

Lycopene has been widely used in the food industry and medical field due to its antioxidant, anti-cancer, and anti-inflammatory properties. However, achieving efficient manufacture of lycopene using chassis cells on an industrial scale remains a major challenge. Herein, we attempted to integrate multiple metabolic engineering strategies to establish an efficient and balanced lycopene biosynthetic system in Saccharomyces cerevisiae. First, the lycopene synthesis pathway was modularized to sequentially enhance the metabolic flux of the Mevalonate pathway, the acetyl-CoA supply module, and lycopene exogenous enzymatic module...

Escherichia coli were engineered to selectively adsorb and recover lithium from the environment by employing bacterial cell surface display strategy. Lithium binding peptide LBP1 was integrated to the Escherichia coli membrane protein OmpC. The effect of environmental conditions on the adsorption of lithium by recombinant strain was evaluated, and lithium particles on cellular surface was analysed by FE-SEM and XRD. To elevate the lithium adsorption, dimeric, trimeric and tetrameric repeats of the LBP1 peptide was constructed and displayed on the surface of E...

Microbes typically live in complex habitats, where they need to rapidly adapt to continuously changing growth conditions. To do so, they produce an astonishing array of natural products with diverse structures and functions. Actinobacteria stand out for their prolific production of bioactive molecules, including antibiotics, anticancer agents, antifungals and immunosuppressants. Attention has been directed especially towards identification of the compounds they produce and mining of the large diversity of biosynthetic gene clusters (BGCs) in their genomes...

Design of Experiments (DoE) is a term used to describe the application statistical approaches to interrogate the impact of many variables on the performance of a multivariate system. It is commonly used for process optimization in fields such as chemical engineering and material science. Recent advances in the ability to quantitatively control the expression of genes in biological systems opens up the possibility to apply DoE for genetic optimization. In this review targeted to genetic and metabolic engineers, we introduce several approaches in DoE at a high-level and describe instances wherein these were applied to interrogate or optimize engineered genetic systems...

The demand for discovering novel microbial secondary metabolites is growing to address the limitations in bioactivities such as antibacterial, antifungal, anticancer, anthelmintic, and immunosuppressive functions. Among microbes, the genus Streptomyces holds particular significance for secondary metabolite discovery. Each Streptomyces species typically encodes approximately 30 secondary metabolite biosynthetic gene clusters within its genome, which are mostly uncharacterized in terms of their products and bioactivities...

The Gram-negative beta-proteobacterium Cupriavidus necator is a chemolithotroph that can convert CO2 into biomass. C. necator has been engineered to produce a variety of high-value chemicals in the past. However, there is still a lack of a well-characterized toolbox for gene expression and genome engineering. Development and optimization of biosynthetic pathways in metabolically engineered microorganisms necessitates control of gene expression via functional genetic elements such as promoters, ribosome binding sites (RBSs), and codon-optimization...

Agricultural waste valorisation provides a sustainable solution to waste management and combining waste utilisation with commodity production allows for responsible production processes. Recombinant Aspergillus niger D15 strains expressing fungal endoglucanases (Trichoderma reesei eg1 and eg2 and Aspergillus carneus aceg) were evaluated for the ability to utilise lactose as a carbon source to determine whether dairy waste could be used as a feedstock for enzyme production. The recombinant A. niger D15[eg1]PyrG, D15[eg2]PyrG and D15[aceg]PyrG strains produced maximum endoglucanase activities of 34, 54, and 34 U/mL, respectively on lactose and 23, 27, and 22 U/mL, respectively on whey...

As a key molecular scaffold for various flavonoids, naringenin is a value-added chemical with broad pharmaceutical applicability. For efficient production of naringenin from acetate, it is crucial to precisely regulate the carbon flux of the OAA-PEP regulatory node through appropriate pckA expression control, as excessive overexpression of pckA can cause extensive loss of OAA and metabolic imbalance. However, considering the critical impact of pckA on naringenin biosynthesis, the conventional strategy of transcriptional regulation of gene expression is limited in its ability to cover the large and balanced solution space, which could result in suboptimal naringenin production...

Despite their prevalent use in drug discovery and protein biochemistry, non-canonical amino acids are still challenging to synthesize through purely chemical means. In recent years, biocatalysis has emerged as a transformative paradigm for small molecule synthesis. One strategy to further empower biocatalysis is to use it in combination with modern chemical reactions and take advantage of the strengths of each method to enable access to challenging structural motifs that are previously unattainable using each method alone...

The platensimycin (PTM), platencin (PTN), and platensilin (PTL) family of natural products continues to inspire the discovery of new chemistry, enzymology, and medicine. Engineered production of this emerging family of natural products however remains laborious due to the lack of practical systems to manipulate their biosynthesis in the native producing Streptomyces platensis species. Here we report solving this technology gap by implementing a CRISPR-Cas9 system in Streptomyces platensis CB00739 to develop an expedient method to manipulate the PTM, PTN, and PTL biosynthetic machinery in vivo...

Amylosucrase (EC 2.4.1.4) is a versatile enzyme with significant potential in biotechnology and food production. To facilitate its efficient preparation, a novel expression strategy was implemented in Bacillus licheniformis for the secretory expression of Neisseria polysaccharea amylosucrase (NpAS). The host strain B. licheniformis CBBD302 underwent genetic modification through the deletion of sacB, a gene responsible for encoding levansucrase that synthesizes extracellular levan from sucrose, resulting in a levan-deficient strain, B...

Out of the 166 articles published in Journal of Industrial Microbiology and Biotechnology (JIMB) in 2019-2020 (not including special issues or review articles), 51 of them used a statistical test to compare two or more means. The most popular test was the (Standard) t-test, which often was used to compare several pairs of means. Other statistical procedures used included Fisher's Least Significant Difference (LSD), Tukey's Honest Significant Difference (HSD), and Welch's t-test; and to a lesser extent Bonferroni, Duncan's Multiple Range, Student-Newman-Keuls, and Kruskal-Wallis tests...

No abstract text is available yet for this article.

Monoterpene indole alkaloids (MIAs) are a class of natural products comprised of thousands of structurally unique bioactive compounds with significant therapeutic values. Due to difficulties associated with isolation from native plant species and organic synthesis of these structurally complex molecules, microbial production of MIAs using engineered hosts are highly desired. In this work, we report the engineering of fully integrated Saccharomyces cerevisiae strains that allow de novo access to strictosidine, the universal precursor to thousands of MIAs at 30-40 mg/L...

Two new macrocyclic secondary metabolites, glycosyl-migrastatin (1) and 5-hydroxy-migrastatin (2), were isolated from a gut bacterium Kitasatospora sp. JL24 in dung beetle Onthophagus lenzii. Based on a comprehensive analysis of the NMR, MS, and UV spectroscopic data, the planar structures of 1 and 2 were successfully identified as new candidates for migrastatin. Compound 1 was the first glycosylated member of the migrastatin family. The absolute configuration of the sugar moiety was determined to be d-glucose through the analysis of coupling constants and ROESY correlations, followed by chromatographic chemical derivatization and comparison with authentic d- and l-glucose...

Secondary metabolites (SMs) are biologically active small molecules, many of which are medically valuable. Fungal genomes contain vast numbers of SM biosynthetic gene clusters (BGCs) with unknown products, suggesting that huge numbers of valuable SMs remain to be discovered. It is challenging, however, to identify SM BGCs, among the millions present in fungi, that produce useful compounds. One solution is resistance gene-guided genome mining, which takes advantage of the fact that some BGCs contain a gene encoding a resistant version of the protein targeted by the compound produced by the BGC...

Natural products have found important applications in the pharmaceutical and agricultural sectors. In bacteria, the genes that encode the biosynthesis of natural products are often colocalized in the genome, forming biosynthetic gene clusters. It has been predicted that only 3% of natural products encoded in bacterial genomes have been discovered thus far, in part because gene clusters may be poorly expressed under laboratory conditions. Heterologous expression can help convert bioinformatics predictions into products...

Microbial natural products are specialized metabolites that are sources of many bioactive compounds including antibiotics, antifungals, antiparasitics, anticancer agents, and probes of biology. The assembly of libraries of producers of natural products has traditionally been the province of the pharmaceutical industry. This sector has gathered significant historical collections of bacteria and fungi to identify new drug leads with outstanding outcomes-upwards of 60% of drug scaffolds originate from such libraries...