Covering 2005–2024
Daptomycin is a clinically important antibiotic that treats Gram-positive infections of skin and skin structure, bacteremia, and right-sided endocarditis, including those caused by methicillin-resistant Staphylococcus aureus (MRSA). Daptomycin is now generic, and many companies are involved in manufacturing and commercializing this life-saving medicine. There has been much recent interest in improving the daptomycin fermentation of Streptomyces roseosporus by mutagenesis, metabolic engineering, and synthetic biology methods. The genome sequences of two strains discovered and developed at Eli Lilly and Company, a wild-type low-producer and a high-producer induced by N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) mutagenesis, are available for comparitive studies. DNA sequence analysis of the daptomycin biosynthetic gene clusters (BGCs) from these strains indicates that the high producer has two mutations in a large promoter region that drives the transcription of a giant multicistronic mRNA that includes all nine genes involved in daptomycin biosynthesis. The locations of translational start and stop codons strongly suggest that all nine genes are translationally coupled by overlapping stop and start codons or by 70S ribosome scanning. This report also reviews recent studies on this promoter region that have identified at least ten positive or negative regulatory genes suitable to manipulate by metabolic engineering, synthetic biology and focused mutagenesis for strain improvement. Improvements in daptomycin production will also enable high-level production of novel lipopeptide antibiotics identified by genome mining and combinatorial biosynthesis, and accelerate clinical and commercial development of superior lipopeptide antibiotics.
Covering: 1977 to presentArsenic is widely distributed throughout terrestrial and aquatic environments, mainly in highly toxic inorganic forms. To adapt to environmental inorganic arsenic, bacteria have evolved ubiquitous arsenic metabolic strategies by combining arsenite methylation and related redox reactions, which have been extensively studied. Recent reports have shown that some bacteria have specific metabolic pathways associated with structurally and biologically unique organoarsenic natural products. In this highlight, by exemplifying the cases of oxo-arsenosugars, arsinothricin, and bisenarsan, we summarize recent advances in the identification and biosynthesis of bacterial organoarsenic natural products. We also discuss the potential discoveries of novel arsenic-containing natural products of bacterial origins.
Artificial intelligence (AI) is accelerating how we conduct science, from folding proteins with AlphaFold and summarizing literature findings with large language models, to annotating genomes and prioritizing newly generated molecules for screening using specialized software. However, the application of AI to emulate human cognition in natural product research and its subsequent impact has so far been limited. One reason for this limited impact is that available natural product data is multimodal, unbalanced, unstandardized, and scattered across many data repositories. This makes natural product data challenging to use with existing deep learning architectures that consume fairly standardized, often non-relational, data. It also prevents models from learning overarching patterns in natural product science. In this Viewpoint, we address this challenge and support ongoing initiatives aimed at democratizing natural product data by collating our collective knowledge into a knowledge graph. By doing so, we believe there will be an opportunity to use such a knowledge graph to develop AI models that can truly mimic natural product scientists' decision-making.
Retraction of ‘Recent advances in total synthesis of protoberberine and chiral tetrahydroberberine alkaloids’ by Zhen-Xi Niu et al., Nat. Prod. Rep., 2024, https://doi.org/10.1039/d4np00016a.
Covering the period 1965-2024Total synthesis has been defined as the art and science of making the molecules of living Nature in the laboratory, and by extension, their analogues. At the extremes, specialised metabolites can be created by total chemical synthesis or by total biosynthesis. In this review we explore the advantages and disadvantages of these two approaches using quantitative methodology that combines measures of molecular complexity, molecular weight and fraction of sp3 centres for bioactive fungal metabolites. Total biosynthesis usually involves fewer chemical steps and those steps move more directly to the target than comparable total chemical synthesis. However, total biosynthesis currently lacks the flexibility of chemical synthesis and the ability to easily diversify synthetic routes.