Biotechnology for Biofuels最新文献

{"title":"Transcriptomic and metabolic changes in Trichoderma reesei caused by mutation in xylanase regulator 1 (xyr1)","authors":"Emmi Sveholm,&nbsp;Hans Mattila,&nbsp;Nina Aro,&nbsp;Mari Valkonen,&nbsp;Tanja Paasela,&nbsp;Tiina M. Pakula","doi":"10.1186/s13068-024-02556-8","DOIUrl":"10.1186/s13068-024-02556-8","url":null,"abstract":"<div><h3>Background</h3><p><i>Trichoderma reesei</i> is known for its ability to produce large amounts of extracellular proteins and is one of the most important industrially used filamentous fungus. Xylanase regulator 1 (XYR1) is the master regulator responsible for the activation of cellulase and hemicellulase gene expression under inducing conditions. It has been reported that strains with point mutations in certain areas of <i>xyr1</i> bypass the need for inducing carbon source, allowing high (hemi)cellulase production even in the presence of glucose. These mutations also change the profile of produced proteins, shifting it more towards xylanase production, and increase the overall protein production in inducing conditions. However, how these mutations alter the metabolism and other cellular processes to cause these changes remains unclear.</p><h3>Results</h3><p>In this study, we aimed to explore changes caused by a point mutation in <i>xyr1</i> on transcriptomic and metabolic level to better understand the reasons behind the increased protein production in both repressing glucose and inducing lactose conditions. As expected, the expression of many carbohydrate-active enzyme (CAZy) genes was increased in the <i>xyr1</i> mutant in both conditions. However, their induction was higher under inducing conditions. The <i>xyr1</i> mutant strain built more biomass and produced more extracellular proteins during growth on lactose compared to the wild type <i>xyr1</i> strain. Genes involved in oxidoreductive D-galactose catabolism pathway were upregulated in the <i>xyr1</i> mutant strain, potentially contributing to the more efficient utilization of lactose. In addition to CAZy genes, clustering and enrichment analysis showed over-representation of mitochondria-related Gene Ontology terms in clusters where gene expression was higher in the <i>xyr1</i> mutant, indicating that mitochondria play a role in the altered metabolic state associated with the <i>xyr1</i> mutation. Metabolomics revealed that free tyrosine was more abundant in the <i>xyr1</i> mutant strain in all measured timepoints, whereas multiple fatty acids were less abundant in the mutant strain on glucose.</p><h3>Conclusions</h3><p>The results contribute to more in-depth knowledge on <i>T. reesei</i> physiology growing under inducing and repressing carbon sources and gives new insights on the function of the master regulator XYR1. The vast data generated serve as a source for new targets for improved protein production.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02556-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141725740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An integrated QTL and RNA-seq analysis revealed new petal morphology loci in Brassica napus L.","authors":"Huaixin Li,&nbsp;Yutian Xia,&nbsp;Wang Chen,&nbsp;Yanru Chen,&nbsp;Xin Cheng,&nbsp;Hongbo Chao,&nbsp;Shipeng Fan,&nbsp;Haibo Jia,&nbsp;Maoteng Li","doi":"10.1186/s13068-024-02551-z","DOIUrl":"10.1186/s13068-024-02551-z","url":null,"abstract":"<div><h3>Background</h3><p>Rapeseed (<i>Brassica napus</i> L.) is one of the most important oil crops and a wildly cultivated horticultural crop. The petals of <i>B. napus</i> serve to protect the reproductive organs and attract pollinators and tourists. Understanding the genetic basis of petal morphology regulation is necessary for <i>B. napus</i> breeding.</p><h3>Results</h3><p>In the present study, the quantitative trait locus (QTL) analysis for six <i>B. napus</i> petal morphology parameters in a double haploid (DH) population was conducted across six microenvironments. A total of 243 QTLs and five QTL hotspots were observed, including 232 novel QTLs and three novel QTL hotspots. The spatiotemporal transcriptomic analysis of the diversiform petals was also conducted, which indicated that the expression of plant hormone metabolic and cytoskeletal binding protein genes was variant among diversiform petals.</p><h3>Conclusions</h3><p>The integration of QTL and RNA-seq analysis revealed that plant hormones (including cytokinin, auxin, and gibberellin) and cytoskeleton were key regulators of the petal morphology. Subsequently, 61 high-confidence candidate genes of petal morphology regulation were identified, including <i>Bn.SAUR10</i>, <i>Bn.ARF18</i>, <i>Bn.KIR1</i>, <i>Bn.NGA2</i>, <i>Bn.PRF1</i>, and <i>Bn.VLN4</i>. The current study provided novel QTLs and candidate genes for further breeding <i>B. napus</i> varieties with diversiform petals.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02551-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141725299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzymatic hydrolysis of waste streams originating from wastewater treatment plants","authors":"Ruta Zarina,&nbsp;Linda Mezule","doi":"10.1186/s13068-024-02553-x","DOIUrl":"10.1186/s13068-024-02553-x","url":null,"abstract":"<div><h3>Background</h3><p>Achieving climate neutrality is a goal that calls for action in all sectors. The requirements for improving waste management and reducing carbon emissions from the energy sector present an opportunity for wastewater treatment plants (WWTPs) to introduce sustainable waste treatment practices. A common biotechnological approach for waste valorization is the production of sugars from lignocellulosic waste biomass via biological hydrolysis. WWTPs produce waste streams such as sewage sludge and screenings which have not yet been fully explored as feedstocks for sugar production yet are promising because of their carbohydrate content and the lack of lignin structures. This study aims to explore the enzymatic hydrolysis of various waste streams originating from WWTPs by using a laboratory-made and a commercial cellulolytic enzyme cocktail for the production of sugars. Additionally, the impact of lipid and protein recovery from sewage sludge prior to the hydrolysis was assessed.</p><h3>Results</h3><p>Treatment with a laboratory-made enzyme cocktail produced by <i>Irpex lacteus</i> (IL) produced 31.2 mg sugar per g dry wastewater screenings. A commercial enzyme formulation released 101 mg sugar per g dry screenings, corresponding to 90% degree of saccharification. There was an increase in sugar levels for all sewage substrates during the hydrolysis with IL enzyme. Lipid and protein recovery from primary and secondary sludge prior to the hydrolysis with IL enzyme was not advantageous in terms of sugar production.</p><h3>Conclusions</h3><p>The laboratory-made fungal IL enzyme showed its versatility and possible application beyond the typical lignocellulosic biomass. Wastewater screenings are well suited for valorization through sugar production by enzymatic hydrolysis. Saccharification of screenings represents a viable strategy to divert this waste stream from landfill and achieve the waste treatment and renewable energy targets set by the European Union. The investigation of lipid and protein recovery from sewage sludge showed the challenges of integrating resource recovery and saccharification processes.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02553-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141725300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Balancing pH and yield: exploring itaconic acid production in Ustilago cynodontis from an economic perspective","authors":"Philipp Ernst,&nbsp;Katharina Maria Saur,&nbsp;Robert Kiefel,&nbsp;Paul-Joachim Niehoff,&nbsp;Ronja Weskott,&nbsp;Jochen Büchs,&nbsp;Andreas Jupke,&nbsp;Nick Wierckx","doi":"10.1186/s13068-024-02550-0","DOIUrl":"10.1186/s13068-024-02550-0","url":null,"abstract":"<div><h3>Background</h3><p>Itaconic acid is a promising bio-based building block for the synthesis of polymers, plastics, fibers and other materials. In recent years, <i>Ustilago cynodontis</i> has emerged as an additional itaconate producing non-conventional yeast, mainly due to its high acid tolerance, which significantly reduces saline waste coproduction during fermentation and downstream processing. As a result, this could likely improve the economic viability of the itaconic acid production process with Ustilaginaceae.</p><h3>Results</h3><p>In this study, we characterized a previously engineered itaconate hyper-producing <i>Ustilago cynodontis</i> strain in controlled fed-batch fermentations to determine the minimal and optimal pH for itaconate production. Under optimal fermentation conditions, the hyper-producing strain can achieve the theoretical maximal itaconate yield during the production phase in a fermentation at pH 3.6, but at the expense of considerable base addition. Base consumption is strongly reduced at the pH of 2.8, but at cost of production yield, titer, and rate. A techno-economic analysis based on the entire process demonstrated that savings due to an additional decrease in pH control reagents and saline waste costs cannot compensate the yield loss observed at the highly acidic pH value 2.8.</p><h3>Conclusions</h3><p>Overall, this work provides novel data regarding the balancing of yield, titer, and rate in the context of pH, thereby contributing to a better understanding of the itaconic acid production process with <i>Ustilago cynodontis</i>, especially from an economic perspective.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11253337/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141636072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Separate hydrolysis and fermentation of softwood bark pretreated with 2-naphthol by steam explosion","authors":"Andreas Averheim,&nbsp;Stefan Stagge,&nbsp;Leif J. Jönsson,&nbsp;Sylvia H. Larsson,&nbsp;Mikael Thyrel","doi":"10.1186/s13068-024-02552-y","DOIUrl":"10.1186/s13068-024-02552-y","url":null,"abstract":"<div><h3>Background</h3><p>2-Naphthol, a carbocation scavenger, is known to mitigate lignin condensation during the acidic processing of lignocellulosic biomass, which may benefit downstream processing of the resulting materials. Consequently, various raw materials have demonstrated improved enzymatic saccharification yields for substrates pretreated through autohydrolysis and dilute acid hydrolysis in the presence of 2-naphthol. However, 2-naphthol is toxic to ethanol-producing organisms, which may hinder its potential application. Little is known about the implications of 2-naphthol in combination with the pretreatment of softwood bark during continuous steam explosion in an industrially scalable system.</p><h3>Results</h3><p>The 2-naphthol-pretreated softwood bark was examined through spectroscopic techniques and subjected to separate hydrolysis and fermentation along with a reference excluding the scavenger and a detoxified sample washed with ethanol. The extractions of the pretreated materials with water resulted in a lower aromatic content in the extracts and stronger FTIR signals, possibly related to guaiacyl lignin, in the nonextractable residue when 2-naphthol was used during pretreatment. In addition, cyclohexane/acetone (9:1) extraction revealed the presence of pristine 2-naphthol in the extracts and increased aromatic content of the nonextractable residue detectable by NMR for the scavenger-pretreated materials. Whole-slurry enzymatic saccharification at 12% solids loading revealed that elevated saccharification recoveries after 48 h could not be achieved with the help of the scavenger. Glucose concentrations of 16.9 (reference) and 15.8 g/l (2-naphthol) could be obtained after 48 h of hydrolysis. However, increased inhibition during fermentation of the scavenger-pretreated hydrolysate, indicated by yeast cell growth, was slight and could be entirely overcome by the detoxification stage. The ethanol yields from fermentable sugars after 24 h were 0.45 (reference), 0.45 (2-naphthol), and 0.49 g/g (2-naphthol, detoxified).</p><h3>Conclusion</h3><p>The carbocation scavenger 2-naphthol did not increase the saccharification yield of softwood bark pretreated in an industrially scalable system for continuous steam explosion. On the other hand, it was shown that the scavenger's inhibitory effects on fermenting microorganisms can be overcome by controlling the pretreatment conditions to avoid cross-inhibition or detoxifying the substrates through ethanol washing. This study underlines the need to jointly optimize all the main processing steps.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11253379/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141636073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility study on heterotrophic utilization of galactose by Chlorella sorokiniana and promotion of galactose utilization through mixed carbon sources culture","authors":"Shengjie Wu,&nbsp;Xiao Cheng,&nbsp;Qinyun Xu,&nbsp;Shikai Wang","doi":"10.1186/s13068-024-02547-9","DOIUrl":"10.1186/s13068-024-02547-9","url":null,"abstract":"<div><h3>Background</h3><p>The development of alternative carbon sources is important for reducing the cost of heterotrophic microalgae cultivation. Among cheap feedstocks, galactose is one of the most abundant sugars and can be easily obtained from many natural biomasses. However, it is generally difficult to be utilized by microalgae. In addition, the mechanism of its low utilization efficiency in heterotrophic cultivation is still unknown.</p><h3>Results</h3><p>Among seven tested carbon sources, only glucose and acetate could be efficiently utilized by <i>C. sorokiniana</i> in heterotrophic cultivation while there were no apparent signs of utilization of other carbohydrates, including galactose, in regular heterotrophic cultivation. However, galactose could be utilized in cultures with high inoculation sizes. This confirmed that <i>C. sorokiniana</i> has a complete pathway for transporting and assimilating galactose under dark conditions, but the rate of galactose utilization is quite low. In addition, the galactose utilization was greatly enhanced in mixotrophic cultures, which indicated that galactose utilization could be enhanced by additional pathways that can enhance cell growth. Based on above results, a mixed carbon source culture strategy was proposed to improve the utilization rate of galactose, and a significant synergistic effect on cell growth was achieved in cultures using a mixture of galactose and acetate.</p><h3>Conclusions</h3><p>This study indicated that the galactose metabolism pathway may not be inherently deficient in Chlorophyta. However, its utilization rate was too low to be detected in regular heterotrophic cultivation. Mixed carbon source culture strategy was confirmed effective to improve the utilization rate of galactose. This study contributes to a deeper understanding of the utilization ability of difficultly utilized substrates in the heterotrophic cultivation of microalgae, which is of great significance for reducing the cost of heterotrophic cultivation of microalgae.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11253373/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141629541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deciphering the genetic landscape of enhanced poly-3-hydroxybutyrate production in Synechocystis sp. B12","authors":"Anna Santin,&nbsp;Flavio Collura,&nbsp;Garima Singh,&nbsp;Maria Silvia Morlino,&nbsp;Edoardo Bizzotto,&nbsp;Alessandra Bellan,&nbsp;Ameya Pankaj Gupte,&nbsp;Lorenzo Favaro,&nbsp;Stefano Campanaro,&nbsp;Laura Treu,&nbsp;Tomas Morosinotto","doi":"10.1186/s13068-024-02548-8","DOIUrl":"10.1186/s13068-024-02548-8","url":null,"abstract":"<div><h3>Background</h3><p>Microbial biopolymers such as poly-3-hydroxybutyrate (PHB) are emerging as promising alternatives for sustainable production of biodegradable bioplastics. Their promise is heightened by the potential utilisation of photosynthetic organisms, thus exploiting sunlight and carbon dioxide as source of energy and carbon, respectively. The cyanobacterium <i>Synechocystis</i> sp. B12 is an attractive candidate for its superior ability to accumulate high amounts of PHB as well as for its high-light tolerance, which makes it extremely suitable for large-scale cultivation. Beyond its practical applications, B12 serves as an intriguing model for unravelling the molecular mechanisms behind PHB accumulation.</p><h3>Results</h3><p>Through a multifaceted approach, integrating physiological, genomic and transcriptomic analyses, this work identified genes involved in the upregulation of chlorophyll biosynthesis and phycobilisome degradation as the possible candidates providing <i>Synechocystis</i> sp. B12 an advantage in growth under high-light conditions. Gene expression differences in pentose phosphate pathway and acetyl-CoA metabolism were instead recognised as mainly responsible for the increased <i>Synechocystis</i> sp. B12 PHB production during nitrogen starvation. In both response to strong illumination and PHB accumulation, <i>Synechocystis</i> sp. B12 showed a metabolic modulation similar but more pronounced than the reference strain, yielding in better performances.</p><h3>Conclusions</h3><p>Our findings shed light on the molecular mechanisms of PHB biosynthesis, providing valuable insights for optimising the use of <i>Synechocystis</i> in economically viable and sustainable PHB production. In addition, this work supplies crucial knowledge about the metabolic processes involved in production and accumulation of these molecules, which can be seminal for the application to other microorganisms as well.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11253406/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141629539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineering cyanobacteria as a new platform for producing taxol precursors directly from carbon dioxide","authors":"Jialing Zhong,&nbsp;Yushu Wang,&nbsp;Zhuoyang Chen,&nbsp;Yaliqin Yalikun,&nbsp;Lin He,&nbsp;Tiangang Liu,&nbsp;Gang Ma","doi":"10.1186/s13068-024-02555-9","DOIUrl":"10.1186/s13068-024-02555-9","url":null,"abstract":"<div><p>Taxol serves as an efficient natural anticancer agent with extensive applications in the treatment of diverse malignancies. Although advances in synthetic biology have enabled the de novo synthesis of taxol precursors in various microbial chassis, the total biosynthesis of taxol remains challengable owing to the restricted oxidation efficiency in heterotrophic microbes. Here, we engineered <i>Synechocystis</i> sp. PCC 6803 with modular metabolic pathways consisting of the methylerythritol phosphate pathway enzymes and taxol biosynthetic enzymes for production of taxadiene-5α-ol (T5α-ol), the key oxygenated intermediate of taxol. The best strain DIGT-P560 produced up to 17.43 mg/L of oxygenated taxanes and 4.32 mg/L of T5α-ol. Moreover, transcriptomic analysis of DIGT-P560 revealed that establishing a oxygenated taxane flux may enhance photosynthetic electron transfer efficiency and central metabolism in the engineered strain to ameliorate the metabolic disturbances triggered by the incorporation of exogenous genes. This is the first demonstration of photosynthetic production of taxadiene-5α-ol from CO₂ in cyanobacteria, highlighting the broad prospects of engineered cyanobacteria as bio-solar cell factories for valuable terpenoids production and expanding the ideas for further rational engineering and optimization.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11253407/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141629540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient production of itaconic acid from the single-carbon substrate methanol with engineered Komagataella phaffii","authors":"Manja Mølgaard Severinsen,&nbsp;Simone Bachleitner,&nbsp;Viola Modenese,&nbsp;Özge Ata,&nbsp;Diethard Mattanovich","doi":"10.1186/s13068-024-02541-1","DOIUrl":"10.1186/s13068-024-02541-1","url":null,"abstract":"<div><h3>Background</h3><p>Amidst the escalating carbon dioxide levels resulting from fossil fuel consumption, there is a pressing need for sustainable, bio-based alternatives to underpin future global economies. Single-carbon feedstocks, derived from CO₂, represent promising substrates for biotechnological applications. Especially, methanol is gaining prominence for bio-production of commodity chemicals.</p><h3>Results</h3><p>In this study, we show the potential of <i>Komagataella phaffii</i> as a production platform for itaconic acid using methanol as the carbon source. Successful integration of heterologous genes from <i>Aspergillus terreus</i> (<i>cadA</i>, <i>mttA</i> and <i>mfsA</i>) alongside fine-tuning of the <i>mfsA</i> gene expression, led to promising initial itaconic acid titers of 28 g·L⁻¹ after 5 days of fed-batch cultivation. Through the combined efforts of process optimization and strain engineering strategies, we further boosted the itaconic acid production reaching titers of 55 g·L⁻¹ after less than 5 days of methanol feed, while increasing the product yield on methanol from 0.06 g·g⁻¹ to 0.24 g·g⁻¹.</p><h3>Conclusion</h3><p>Our results highlight the potential of <i>K. phaffii</i> as a methanol-based platform organism for sustainable biochemical production.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02541-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141621947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing monolignol ferulate conjugate levels in poplar lignin via OsFMT1","authors":"Faride Unda,&nbsp;Lisanne de Vries,&nbsp;Steven D. Karlen,&nbsp;Jordan Rainbow,&nbsp;Chengcheng Zhang,&nbsp;Laura E. Bartley,&nbsp;Hoon Kim,&nbsp;John Ralph,&nbsp;Shawn D. Mansfield","doi":"10.1186/s13068-024-02544-y","DOIUrl":"10.1186/s13068-024-02544-y","url":null,"abstract":"<div><h3>Background</h3><p>The phenolic polymer lignin is one of the primary chemical constituents of the plant secondary cell wall. Due to the inherent plasticity of lignin biosynthesis, several phenolic monomers have been shown to be incorporated into the polymer, as long as the monomer can undergo radicalization so it can participate in coupling reactions. In this study, we significantly enhance the level of incorporation of monolignol ferulate conjugates into the lignin polymer to improve the digestibility of lignocellulosic biomass.</p><h3>Results</h3><p>Overexpression of a rice Feruloyl-CoA Monolignol Transferase (<i>FMT</i>), <i>OsFMT1</i>, in hybrid poplar (<i>Populus alba</i> x <i>grandidentata</i>) produced transgenic trees clearly displaying increased cell wall-bound ester-linked ferulate, <i>p-</i>hydroxybenzoate, and <i>p-</i>coumarate, all of which are in the lignin cell wall fraction, as shown by NMR and DFRC. We also demonstrate the use of a novel UV–Vis spectroscopic technique to rapidly screen plants for the presence of both ferulate and <i>p-</i>hydroxybenzoate esters. Lastly we show, via saccharification assays, that the <i>OsFMT1</i> transgenic p oplars have significantly improved processing efficiency compared to wild-type and <i>Angelica sinensis</i>-<i>FMT-expressing</i> poplars.</p><h3>Conclusions</h3><p>The findings demonstrate that <i>OsFMT1</i> has a broad substrate specificity and a higher catalytic efficiency compared to the previously published FMT from <i>Angelica sinensis</i> (<i>AsFMT</i>). Importantly, enhanced wood processability makes <i>OsFMT1</i> a promising gene to optimize the composition of lignocellulosic biomass.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"17 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2024-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02544-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141604658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}