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Category Archives: Biotechnology

Microalgal biomass production pathways: evaluation of life cycle environmental impacts

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Background:
Microalgae are touted as an attractive alternative to traditional forms of biomass for biofuel production, due to high productivity, ability to be cultivated on marginal lands, and potential to utilize carbon dioxide (CO2) from industrial flue gas. This work examines the fossil energy return on investment (EROIfossil), greenhouse gas (GHG) emissions, and direct Water Demands (WD) of producing dried algal biomass through the cultivation of microalgae in Open Raceway Ponds (ORP) for 21 geographic locations in the contiguous United States (U.S.). For each location, comprehensive life cycle assessment (LCA) is performed for multiple microalgal biomass production pathways, consisting of a combination of cultivation and harvesting options.
Results:
Results indicate that the EROIfossil for microalgae biomass vary from 0.38 to 1.08 with life cycle GHG emissions of -46.2 to 48.9 (g CO2 eq/MJ-biomass) and direct WDs of 20.8 to 38.8 (Liters/MJ-biomass) over the range of scenarios analyzed. Further anaylsis reveals that the EROIfossil for production pathways is relatively location invariant, and that algae's life cycle energy balance and GHG impacts are highly dependent on cultivation and harvesting parameters. Contrarily, algae's direct water demands were found to be highly sensitive to geographic location, and thus may be a constraining factor in sustainable algal-derived biofuel production. Additionally, scenarios with promising EROIfossil and GHG emissions profiles are plagued with high technological uncertainty.
Conclusions:
Given the high variability in microalgae's energy and environmental performance, careful evaluation of the algae-to-fuel supply chain is necessary to ensure the long-term sustainability of emerging algal biofuel systems. Alternative production scenarios and technologies may have the potential to reduce the critical demands of biomass production, and should be considered to make algae a viable and more efficient biofuel alternative.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/88

Identification of multiple interacting alleles conferring low glycerol and high ethanol yield in Saccharomyces cerevisiae ethanolic fermentation

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Background:
Genetic engineering of industrial microorganisms often suffers from undesirable side effects on essential functions. Reverse engineering is an alternative strategy to improve multifactorial traits like low glycerol/high ethanol yield in yeast fermentation. Previous rational engineering of this trait always affected essential functions like growth and stress tolerance. We have screened Saccharomyces cerevisiae biodiversity for specific alleles causing lower glycerol/higher ethanol yield, assuming higher compatibility with normal cellular functionality. Previous work identified ssk1E330N...K356N as causative allele in strain CBS6412, which displayed the lowest glycerol/ethanol ratio.
Results:
We have now identified a unique segregant, 26B, that shows similar low glycerol/high ethanol production as the superior parent, but lacks the ssk1E330N...K356N allele. Using segregants from the backcross of 26B with the inferior parent strain, we applied pooled-segregant whole-genome sequence analysis and identified three minor quantitative trait loci (QTLs) linked to low glycerol/high ethanol production. Within these QTLs, we identified three novel alleles of known regulatory and structural genes of glycerol metabolism, smp1R110Q,P269Q, hot1P107S,H274Y and gpd1L164P as causative genes. All three genes separately caused a significant drop in the glycerol/ethanol production ratio, while gpd1L164P appeared to be epistatically suppressed by other alleles in the superior parent. The order of potency in reducing the glycerol/ethanol ratio of the three alleles was: gpd1L164P > hot1P107S,H274Y >= smp1R110Q,P269Q.
Conclusions:
Our results show that natural yeast strains harbor multiple specific alleles of genes controlling essential functions, that are apparently compatible with survival in the natural environment. These newly identified alleles can be used as gene tools for engineering industrial yeast strains with multiple subtle changes, minimizing the risk of negatively affecting other essential functions. The gene tools act at the transcriptional, regulatory or structural gene level, distributing the impact over multiple targets and thus further minimizing possible side-effects. In addition, the results suggest polygenic analysis of complex traits as a promising new avenue to identify novel components involved in cellular functions, including those important in industrial applications.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/87

Saffron (Crocus sativus L.) Biotechnology, Research, Developpement and Collaboration – Video

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Saffron (Crocus sativus L.) Biotechnology, Research, Developpement and Collaboration
Saffron Research Collaboration : +212 67 206 3181 / blkaid@hotmail.com + Laboratories and Professionals (Projects, Exchange, Primers, Engeneering, Molecular ...

By: MOHAMED BEN EL CAID

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Saffron (Crocus sativus L.) Biotechnology, Research, Developpement and Collaboration - Video

Saffron (Crocus sativus) Science Research Collaboration Biotechnology : Genetic variation – Video

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Saffron (Crocus sativus) Science Research Collaboration Biotechnology : Genetic variation
Saffron Research Collaboration : +212 67 206 3181 / blkaid@hotmail.com Biotechnology, Genetic matkers (SSR, RAPD) In vitro culture, Genetic variation, chemic...

By: MOHAMED BEN EL CAID

Originally posted here:
Saffron (Crocus sativus) Science Research Collaboration Biotechnology : Genetic variation - Video

Opinion: Harry Boxer: Watch these two biotechnology stocks – MarketWatch

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President Trump pressed Big Pharma executives to increase U.S. production and lower drug prices.

As biotechnology stocks have been showing momentum following a meeting between President Trump and pharmaceutical executives Tuesday, our two long investments to watch are in that sector. There are also several shorts among our charts to watch to play the potential downside in this near-term, toppy-looking stock market.

Gene-therapy company bluebird bio Inc. BLUE, -0.95% has a strong-looking chart. The stock recently broke out of a wedge pattern, in which its price range had narrowed for two months in essentially a sideways direction. The stock continued the upmove on Tuesday when it popped $5.90, or over 8%, to $74.50, and followed through for another $1.10 on Wednesday to $75.60. The stock is now positioned to challenge its recent high at $79.70 from early December. A break through there could lead to a move into the mid-$80s, followed by a next target in the mid-$90s. With short interest of 9.2 its average volume, the price advance could be further fueled by short covering.

Cara Therapeutics Inc. CARA, -1.50% a cannabis-based biotech, has been steadily climbing since the start of the year. On Wednesday, the stock popped $1.17, or 7.6%, to $16.49 on 4.7 million shares, which is huge volume for this stock, the biggest since mid-November. The stock got as high as $17.20 intraday before pulling back into the close. It is a bit extended near the top of its channel and could pull back and consolidate before its next move, but momentum could carry it a bit further toward $18.

On the short side, Carters Inc. CRI, -0.08% continues lower since its July 2016 top above $112. On Wednesday, shares in the childrens wear retailer were down another $1.05, or 1.3%, to $82.70, on 690,100 shares traded. The stock appears headed toward the bottom of its declining channel in the $73-$74 range.

Signet Jewelers Ltd. SIG, -2.94% is also continuing lower. The stock rallied from the bottom of its declining price channel to the top in the last quarter of 2016, but has since broken down. Shares fell another 66 cents to $77.01 on 1.5 million shares traded on Wednesday. Watch for a test of the late-September low in the $72-$73 range. A takeout of that could drop the stock near its channel bottom in the low- to mid-$60s.

See Harrys video chart analysis on these and other stocks.

The writer has no holdings in any securities mention in this article.

Harry Boxer is the founder of TheTechTrader.com, a live trading room featuring his stock picks, technical market analysis and live chart presentations.

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Opinion: Harry Boxer: Watch these two biotechnology stocks - MarketWatch

Conversion of fatty aldehydes into alk (a/e)nes by in vitro reconstituted cyanobacterial aldehyde-deformylating oxygenase with the cognate electron transfer system

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Background:
Biosynthesis of fatty alk(a/e)ne in cyanobacteria has been considered as a potential basis for the sunlight-driven and carbon-neutral bioprocess producing advanced solar biofuels. Aldehyde-deformylating oxygenase (ADO) is a key enzyme involved in that pathway. The heterologous or chemical reducing systems were generally used in in vitro ADO activity assay. The cognate electron transfer system from cyanobacteria to support ADO activity is still unknown.
Results:
We identified the potential endogenous reducing system including ferredoxin (Fd) and ferredoxin-NADP+ reductase (FNR) to support ADO activity in Synechococcus elongatus PCC7942. ADO (Synpcc7942_1593), FNR (SynPcc7942_0978), and Fd (SynPcc7942_1499) from PCC7942 were cloned, overexpressed, purified, and characterized. ADO activity was successfully supported with the endogenous electron transfer system, which worked more effectively than the heterologous and chemical ones. The results of the hybrid Fd/FNR reducing systems demonstrated that ADO was selective against Fd. And it was observed that the cognate reducing system produced less H2O2 than the heterologous one by 33% during ADO-catalyzed reactions. Importantly, kcat value of ADO 1593 using the homologous Fd/FNR electron transfer system is 3.7-fold higher than the chemical one.
Conclusions:
The cognate electron transfer system from cyanobacteria to support ADO activity was identified and characterized. For the first time, ADO was functionally in vitro reconstituted with the endogenous reducing system from cyanobacteria, which supported greater activity than the surrogate and chemical ones, and produced less H2O2 than the heterologous one. The identified Fd/FNR electron transfer system will be potentially useful for improving ADO activity and further enhancing the biosynthetic efficiency of hydrocarbon biofuels in cyanobacteria.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/86

Metabolic engineering of Caldicellulosiruptor bescii yields increased hydrogen production from lignocellulosic biomass

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Background:
Members of the anaerobic thermophilic bacterial genus Caldicellulosiruptor are emerging candidates for consolidated bioprocessing (CBP) because they are capable of efficiently growing on biomass without conventional pretreatment. C. bescii produces primarily lactate, acetate and hydrogen as fermentation products, and while some Caldicellulosiruptor strains produce small amounts of ethanol C. bescii does not, making it an attractive background to examine the effects of metabolic engineering. The recent development of methods for genetic manipulation has set the stage for rational engineering of this genus for improved biofuel production. Here, we report the first targeted gene deletion, the gene encoding lactate dehydrogenase (ldh), for metabolic engineering of a member of this genus.
Results:
A deletion of the C. bescii L-lactate dehydrogenase gene (ldh) was constructed on a non-replicating plasmid and introduced into the C. bescii chromosome by marker replacement. The resulting strain failed to produce detectable levels of lactate from cellobiose and maltose, instead increasing production of acetate and H2 by 21-34% relative to the wild type and ?pyrFA parent strains. The same phenotype was observed on a real-world substrate – switchgrass (Panicum virgatum). Furthermore, the ldh deletion strain grew to a higher maximum optical density than the wild type on maltose and cellobiose, consistent with the prediction that the mutant would gain additional ATP with increased acetate production.
Conclusions:
Deletion of ldh in C. bescii is the first use of recently developed genetic methods for metabolic engineering of these bacteria. This deletion resulted in a redirection of electron flow from production of lactate to acetate and hydrogen. New capabilities in metabolic engineering combined with intrinsic utilization of lignocellulosic materials position these organisms to provide a new paradigm for consolidated bioprocessing of fuels and other products from biomass.Source:
http://www.biotechnologyforbiofuels.com/content/6/1/85


  1. Biotechnology