Abstract:
:Microalgae hold great promises as sustainable cellular factories for the production of alternative fuels, feeds, and biopharmaceuticals for human health. While the biorefinery approach for fuels along with the coproduction of high-value compounds with industrial, therapeutic, or nutraceutical applications have the potential to make algal biofuels more economically viable, a number of challenges continue to hamper algal production systems at all levels. One such hurdle includes the metabolic trade-off often observed between the increased yields of desired products, such as triacylglycerols (TAG), and the growth of an organism. Initial genetic engineering strategies to improve lipid productivity in microalgae, which focused on overproducing the enzymes involved in fatty acid and TAG biosynthesis or inactivating competing carbon (C) metabolism, have seen some successes albeit at the cost of often greatly reduced biomass. Emergent approaches that aim at modifying the dynamics of entire metabolic pathways by engineering of pertinent transcription factors or signaling networks appear to have successfully achieved a balance between growth and neutral lipid accumulation. However, the biological knowledge of key signaling networks and molecular components linking these two processes is still incomplete in photosynthetic eukaryotes, making it difficult to optimize metabolic engineering strategies for microalgae. Here, we focus on nitrogen (N) starvation of the model green microalga, Chlamydomonas reinhardtii, to present the current understanding of the nutrient-dependent switch between proliferation and quiescence, and the drastic reprogramming of metabolism that results in the storage of C compounds following N starvation. We discuss the potential components mediating the transcriptional repression of cell cycle genes and the establishment of quiescence in Chlamydomonas, and highlight the importance of signaling pathways such as those governed by the target of rapamycin (TOR) and sucrose nonfermenting-related (SnRK) kinases in the coordination of metabolic status with cellular growth. A better understanding of how the cell division cycle is regulated in response to nutrient scarcity and of the signaling pathways linking cellular growth to energy and lipid homeostasis, is essential to improve the prospects of biofuels and biomass production in microalgae.
journal_name
Biotechnol Biofuelsjournal_title
Biotechnology for biofuelsauthors
Takeuchi T,Benning Cdoi
10.1186/s13068-019-1635-0subject
Has Abstractpub_date
2019-12-23 00:00:00pages
292issn
1754-6834pii
1635journal_volume
12pub_type
杂志文章,评审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:Saccharomyces cerevisiae, a key organism used for the manufacture of renewable fuels and chemicals, has been engineered to utilize non-native sugars derived from plant cell walls, such as cellobiose and xylose. However, the rates and efficiencies of these non-native sugar fermentations pale in comparison wit...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-014-0126-6
更新日期:2014-08-27 00:00:00
abstract:BACKGROUND:The microbial community in anaerobic digestion is mainly monitored by means of DNA-based methods. This may lead to incorrect interpretation of the community parameters, because microbial abundance does not necessarily reflect activity. In this research, the difference between microbial community response on ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0652-5
更新日期:2016-11-09 00:00:00
abstract:Background:Cyanobacteria can be metabolically engineered to convert CO2 to fuels and chemicals such as ethylene. A major challenge in such efforts is to optimize carbon fixation and partition towards target molecules. Results:The efe gene encoding an ethylene-forming enzyme was introduced into a strain of the cyanobac...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-020-1653-y
更新日期:2020-01-28 00:00:00
abstract:Background:Cellulose accessibility to cellulases (CAC) is a direct factor determining the enzymatic digestibility of lignocellulosic cellulose. Improving CAC by pretreatment is a prerequisite step for the efficient release of fermentable sugars from biomass cell wall. However, conventional methods to study the porosime...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1105-0
更新日期:2018-04-09 00:00:00
abstract:BACKGROUND:Nitrogen limitation can induce neutral lipid accumulation in microalgae, as well as inhibiting their growth. Therefore, to obtain cultures with both high biomass and high lipid contents, and explore the lipid accumulation mechanisms, we implemented nitrogen deprivation in a model diatom Phaeodactylum tricorn...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-6-67
更新日期:2013-05-04 00:00:00
abstract:BACKGROUND:Simultaneous saccharification and fermentation (SSF) is a promising process for bioconversion of lignocellulosic biomass. High glucan loading for hydrolysis and fermentation is an efficient approach to reduce the capital costs for bio-based products production. The SSF of steam-exploded corn stover (SECS) fo...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-014-0167-x
更新日期:2014-12-04 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:Integration of second-generation (2G) bioethanol production with existing first-generation (1G) production may facilitate commercial production of ethanol from cellulosic material. Since 2G hydrolysates have a low sugar concentration and 1G streams often have to be diluted prior to fermentation, mixing of st...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-6-169
更新日期:2013-11-29 00:00:00
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journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1227-4
更新日期:2018-08-23 00:00:00
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journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1140-x
更新日期:2018-05-12 00:00:00
abstract:Background:Biogenic and biogenic-thermogenic coalbed methane (CBM) are important energy reserves for unconventional natural gas. Thus, to investigate biogenic gas formation mechanisms, a series of fresh coal samples from several representative areas of China were analyzed to detect hydrogen-producing bacteria and metha...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1237-2
更新日期:2018-09-08 00:00:00
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journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-6-134
更新日期:2013-09-16 00:00:00
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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:Alkaline hydrogen peroxide pretreatment catalyzed by Cu(II) 2,2'-bipyridine complexes has previously been determined to substantially improve the enzymatic hydrolysis of woody plants including hybrid poplar as a consequence of moderate delignification. In the present work, cell wall morphological and lignin ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-015-0300-5
更新日期:2015-08-20 00:00:00
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journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1084-1
更新日期:2018-04-02 00:00:00
abstract:BACKGROUND:Pretreatment of lignocellulosic biomass generates a number of undesired degradation products that can inhibit microbial metabolism. Two of these compounds, the furan aldehydes 5-hydroxymethylfurfural (HMF) and 2-furaldehyde (furfural), have been shown to be an impediment for viable ethanol production. In the...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-6-181
更新日期:2013-12-16 00:00:00
abstract:Background:Understanding the extracellular electron transport pathways in cyanobacteria is a major factor towards developing biophotovoltaics. Stressing cyanobacteria cells environmentally and then probing changes in physiology or metabolism following a significant change in electron transfer rates is a common approach...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-020-01788-8
更新日期:2020-08-26 00:00:00
abstract:BACKGROUND:Brown algae are promising feedstocks for biofuel production with inherent advantages of no structural lignin, high growth rate, and no competition for land and fresh water. However, it is difficult for one microorganism to convert all components of brown algae with different oxidoreduction potentials to etha...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0494-1
更新日期:2016-04-01 00:00:00
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journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-019-1378-y
更新日期:2019-02-27 00:00:00
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journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0446-9
更新日期:2016-02-03 00:00:00
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journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1280-z
更新日期:2018-10-11 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:The genome of Pleurotus ostreatus, an important edible mushroom and a model ligninolytic organism of interest in lignocellulose biorefineries due to its ability to delignify agricultural wastes, was sequenced with the purpose of identifying and characterizing the enzymes responsible for lignin degradation. ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-7-2
更新日期:2014-01-03 00:00:00
abstract:BACKGROUND:Due to its capacity to produce large amounts of cellulases, Trichoderma reesei is increasingly been researched in various fields of white biotechnology, especially in biofuel production from lignocellulosic biomass. The commercial enzyme mixtures produced at industrial scales are not well characterized, and ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/1754-6834-1-18
更新日期:2008-12-23 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
abstract:Background:Photosynthetic oleaginous microalgae are promising feedstocks for biofuels. Acyl-CoA:diacylglycerol acyltransferases (DGATs) represent rich sources for engineering microalgal lipid production. The principal activity of DGATs has been defined as a single-function enzyme catalyzing the esterification of diacyl...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-018-1029-8
更新日期:2018-02-09 00:00:00
abstract:Background:2,3-Butanediol (2,3-BDO) is a valuable chemical for industrial applications. Bacteria can produce 2,3-BDO with a high productivity, though most of their classification as pathogens makes them undesirable for the industrial-scale production. Though Saccharomyces cerevisiae (GRAS microorganism) was engineered ...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-019-1545-1
更新日期:2019-08-29 00:00:00
abstract:BACKGROUND:In general, biofuel production involves biomass pretreatment and enzymatic saccharification, followed by the subsequent sugar conversion to biofuel via fermentation. The crucial step in the production of biofuel from biomass is the enzymatic saccharification. Many of the commercial cellulase enzyme cocktails...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-016-0587-x
更新日期:2016-08-22 00:00:00
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...
journal_title:Biotechnology for biofuels
pub_type: 杂志文章
doi:10.1186/s13068-019-1540-6
更新日期:2019-08-20 00:00:00