Abstract:
Background:A consolidated bioprocessing (CBP), where lignocellulose is converted into the desired product(s) in a single fermentative step without the addition of expensive degradative enzymes, represents the ideal solution of renewable routes to chemicals and fuels. Members of the genus Geobacillus are able to grow at elevated temperatures and are able to utilise a wide range of oligosaccharides derived from lignocellulose. This makes them ideally suited to the development of CBP. Results:In this study, we engineered Geobacillus thermoglucosidasius NCIMB 11955 to utilise lignocellulosic biomass, in the form of nitric acid/ammonia treated wheat straw to which expensive hydrolytic enzymes had not been added. Two different strains, BZ9 and BZ10, were generated by integrating the cglT (β-1,4-glucosidase) gene from Thermoanaerobacter brockii into the genome, and localising genes encoding different cellulolytic enzymes on autonomous plasmids. The plasmid of strain BZ10 carried a synthetic cellulosomal operon comprising the celA (Endoglucanase A) gene from Clostridium thermocellum and cel6B (Exoglucanase) from Thermobifida fusca; whereas, strain BZ9 contained a plasmid encoding the celA (multidomain cellulase) gene from Caldicellulosiruptor bescii. All of the genes were successfully expressed, and their encoded products secreted in a functionally active form, as evidenced by their detection in culture supernatants by Western blotting and enzymatic assay. In the case of the C. bescii CelA enzyme, this is one of the first times that the heterologous production of this multi-functional enzyme has been achieved in a heterologous host. Both strains (BZ9 and BZ10) exhibited improved growth on pre-treated wheat straw, achieving a higher final OD600 and producing greater numbers of viable cells. To demonstrate that cellulosic ethanol can be produced directly from lignocellulosic biomass by a single organism, we established our consortium of hydrolytic enzymes in a previously engineered ethanologenic G. thermoglucosidasius strain, LS242. We observed approximately twofold and 1.6-fold increase in ethanol production in the recombinant G. thermoglucosidasius equivalent to BZ9 and BZ10, respectively, compared to G. thermoglucosidasius LS242 strain at 24 h of growth. Conclusion:We engineered G. thermoglucosidasius to utilise a real-world lignocellulosic biomass substrate and demonstrated that cellulosic ethanol can be produced directly from lignocellulosic biomass in one step. Direct conversion of biomass into desired products represents a new paradigm for CBP, offering the potential for carbon neutral, cost-effective production of sustainable chemicals and fuels.
journal_name
Biotechnol Biofuelsjournal_title
Biotechnology for biofuelsauthors
Bashir Z,Sheng L,Anil A,Lali A,Minton NP,Zhang Ydoi
10.1186/s13068-019-1540-6subject
Has Abstractpub_date
2019-08-20 00:00:00pages
199issn
1754-6834pii
1540journal_volume
12pub_type
杂志文章abstract:Background:Xylan is a major hemicellulosic component in the cell walls of higher plants especially in the secondary walls of vascular cells which are playing important roles in physiological processes and overall mechanical strength. Being the second most abundant cell wall polymer after cellulose, xylan is an abundant...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-017-0935-5
更新日期:2017-11-30 00:00:00
abstract:BACKGROUND:Microbial synthesis of oleochemicals derived from native fatty acid (FA) metabolism has presented significant advances in recent years. Even so, native FA biosynthetic pathways often provide a narrow variety of usually linear hydrocarbons, thus yielding end products with limited structural diversity. To over...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0631-x
更新日期:2016-10-14 00:00:00
abstract:BACKGROUND:Termite lignocellulose digestion is achieved through a collaboration of host plus prokaryotic and eukaryotic symbionts. In the present work, we took a combined host and symbiont metatranscriptomic approach for investigating the digestive contributions of host and symbiont in the lower termite Reticulitermes ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-2-25
更新日期:2009-10-15 00:00:00
abstract:Background:Beer is the most popular alcoholic beverage worldwide. In the manufacture of beer, various by-products and residues are generated, and the most abundant (85% of total by-products) are spent grains. Thanks to its high (hemi)cellulose content (about 50% w/w dry weight), this secondary raw material is attractiv...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-019-1383-1
更新日期:2019-03-05 00:00:00
abstract:Background:Biofilms are cell communities wherein cells are embedded in a self-produced extracellular polymeric substances (EPS). The biofilm of Clostridium acetobutylicum confers the cells superior phenotypes and has been extensively exploited to produce a variety of liquid biofuels and bulk chemicals. However, little ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1316-4
更新日期:2018-11-20 00:00:00
abstract:BACKGROUND:Higher ratios of syringyl-to-guaiacyl (S/G) lignin components of Populus were shown to improve sugar release by enzymatic hydrolysis using commercial blends. Cellulolytic microbes are often robust biomass hydrolyzers and may offer cost advantages; however, it is unknown whether their activity can also be sig...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0445-x
更新日期:2016-02-04 00:00:00
abstract:BACKGROUND:Cyanobacteria are an attractive candidate for the production of biofuel because of their ability to capture carbon dioxide by photosynthesis and grow on non-arable land. However, because huge quantities of water are required for cultivation, strict water management is one of the greatest issues in algae- and...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-7-56
更新日期:2014-04-09 00:00:00
abstract:BACKGROUND:Production of valuable metabolites by Yarrowia lipolytica using renewable raw materials is of major interest for sustainable food and energy. Galactose is a monosaccharide found in galactomannans, hemicelluloses, gums, and pectins. RESULTS:Yarrowia lipolytica was found to express all the Leloir pathway gene...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-015-0370-4
更新日期:2015-11-25 00:00:00
abstract:BACKGROUND:Globally, the development of a cost-effective long-term renewable energy infrastructure is one of the most challenging problems faced by society today. Microalgae are rich in potential biofuel substrates such as lipids, including triacylglycerols (TAGs). Some of these algae also biosynthesize small molecule ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-7-62
更新日期:2014-04-15 00:00:00
abstract:BACKGROUND:Enzymatic degradation of plant biomass requires a complex mixture of many different enzymes. Like most fungi, thermophilic Myceliophthora species therefore have a large set of enzymes targeting different linkages in plant polysaccharides. The majority of these enzymes have not been functionally characterized...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0460-y
更新日期:2016-02-20 00:00:00
abstract:BACKGROUND:Non-productive cellulase adsorption onto lignin has always been deemed to negatively affect the enzymatic hydrolysis of lignocellulosic feedstocks. Therefore, understanding enzyme-lignin interactions is essential for the development of enzyme mixtures, the processes of lignocellulose hydrolysis, and the gene...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-7-38
更新日期:2014-03-14 00:00:00
abstract:BACKGROUND:Thermochemical pretreatment of lignocellulose is crucial to bioconversion in the fields of biorefinery and biofuels. However, the enzyme inhibitors in pretreatment hydrolysate make solid substrate washing and hydrolysate detoxification indispensable prior to enzymatic hydrolysis. Sulfite pretreatment to over...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-6-156
更新日期:2013-11-05 00:00:00
abstract:BACKGROUND:Low- and high-affinity glucose transport system is a conserved strategy of microorganism to cope with environmental glucose fluctuation for their growth and competitiveness. In Neurospora crassa, the dual-affinity glucose transport system consists of a low-affinity glucose transporter GLT-1 and two high-affi...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-021-01877-2
更新日期:2021-01-28 00:00:00
abstract:BACKGROUND:Bioaugmentation or an addition of the desired microorganisms or specialized microbial strains into the anaerobic digesters can enhance the performance of microbial community in the hydrogen production process. Most of the studies focused on a bioaugmentation of native microorganisms capable of producing hydr...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-015-0375-z
更新日期:2015-11-25 00:00:00
abstract:Background:The extremely thermophilic bacterium Caldicellulosiruptor lactoaceticus can degrade and metabolize untreated lignocellulosic biomass containing xylan. The mechanism of the bacterium for degradation of insoluble xylan in untreated biomass has not been revealed. Results:In the present study, the only annotate...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-019-1480-1
更新日期:2019-06-08 00:00:00
abstract:BACKGROUND:In addition to efficient pentose utilization, high inhibitor tolerance is a key trait required in any organism used for economically viable industrial bioethanol production with lignocellulose biomass. Although recent work has succeeded in establishing efficient xylose fermentation in robust industrial Sacch...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-6-120
更新日期:2013-08-26 00:00:00
abstract:BACKGROUND:The production of biofuels in photosynthetic microalgae and cyanobacteria is a promising alternative to the generation of fuels from fossil resources. To be economically competitive, producer strains need to be established that synthesize the targeted product at high yield and over a long time. Engineering c...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-7-21
更新日期:2014-02-06 00:00:00
abstract:BACKGROUND:Replacing the energy-intensive evaporation of stillage by anaerobic digestion is one way of decreasing the energy demand of the lignocellulosic biomass to the ethanol process. The biogas can be upgraded and sold as transportation fuel, injected directly into the gas grid or be incinerated on-site for combine...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-3-21
更新日期:2010-09-15 00:00:00
abstract:BACKGROUND:Consolidated bioprocessing (CBP) of lignocellulosic biomass to hydrogen offers great potential for lower cost and higher efficiency compared to processes featuring dedicated cellulase production. Current studies on CBP-based hydrogen production mainly focus on using the thermophilic cellulolytic bacterium Cl...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-7-82
更新日期:2014-06-03 00:00:00
abstract:BACKGROUND:Large-scale production of effective cellulose hydrolytic enzymes is the key to the bioconversion of agricultural residues to ethanol. The goal of this study was to develop a rice plant as a bioreactor for the large-scale production of cellulose hydrolytic enzymes via genetic transformation, and to simultaneo...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-4-58
更新日期:2011-12-10 00:00:00
abstract:Background:Cyanobacteria have shown promising potential for the production of various biofuels and chemical feedstocks. Synechococcus elongatus UTEX 2973 is a fast-growing strain with pronounced tolerance to high temperatures and illumination. Hence, this strain appears to be ideal for the development of photosynthetic...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1215-8
更新日期:2018-08-04 00:00:00
abstract:Background:Bioelectrochemical systems (BESs) harness electrons from microbial respiration to generate power or chemical products from a variety of organic feedstocks, including lignocellulosic biomass, fermentation byproducts, and wastewater sludge. In some BESs, such as microbial fuel cells (MFCs), bacteria living in ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1111-2
更新日期:2018-04-23 00:00:00
abstract:BACKGROUND:The model alga Chlamydomonas reinhardtii requires acetate as a co-substrate for optimal production of lipids, and the addition of acetate to culture media has practical and economic implications for algal biofuel production. Here we demonstrate the growth of C. reinhardtii on acetate provided by mutant strai...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-014-0154-2
更新日期:2014-10-18 00:00:00
abstract:Background:Energy crops including Miscanthus provide a storable, portable energy source which can be used to complement a wide range of products and energy generation systems. Miscanthus is predominantly used in Europe as a combustion material for electricity generation but also has the potential for biochemical conver...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1066-3
更新日期:2018-03-14 00:00:00
abstract:BACKGROUND:The production of biofuels and biochemicals from grass-type plant biomass requires a complete utilisation of the plant cellulose and hemicellulosic xylan via enzymatic degradation to their constituent monosaccharides. Generally, physical and/or thermochemical pretreatments are performed to enable access for ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0519-9
更新日期:2016-05-18 00:00:00
abstract:BACKGROUND:Camelina sativa (L.) Crantz, known by such popular names as "gold-of-pleasure" and "false flax," is an alternative oilseed crop for biofuel production and can be grown in harsh environments. Considerable interest is now being given to the new concept of the development of a fusion plant which can be used as ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-7-96
更新日期:2014-06-22 00:00:00
abstract:BACKGROUND:The conversion of biomass-derived sugars via enzymatic hydrolysis for biofuel production is a challenge. Therefore, the search for microorganisms and key enzymes that increase the efficiency of the saccharification of cellulosic substrates remains an important and high-priority area of study. Trichoderma har...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0487-0
更新日期:2016-03-22 00:00:00
abstract:Background:The need for liquid fuels in the transportation sector is increasing, and it is essential to develop industrially sustainable processes that simultaneously address the tri-fold sustainability metrics of technological feasibility, economic viability, and environmental impacts. Biorefineries based on lignocell...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-017-0959-x
更新日期:2017-11-14 00:00:00
abstract:BACKGROUND:Accumulation of recalcitrant oligosaccharides during high-solids loading enzymatic hydrolysis of cellulosic biomass reduces biofuel yields and increases processing costs for a cellulosic biorefinery. Recalcitrant oligosaccharides in AFEX-pretreated corn stover hydrolysate accumulate to the extent of about 18...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-015-0378-9
更新日期:2015-11-26 00:00:00
abstract:Background:Countercurrent saccharification is a promising way to minimize enzyme loading while obtaining high conversions and product concentrations. However, in countercurrent saccharification experiments, 3-4 months are usually required to acquire a single steady-state data point. To save labor and time, simulation o...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-019-1517-5
更新日期:2019-07-11 00:00:00