Biotech bugs turn indigo blue in a green way.
Jeans dyed blue by bacteria may soon be swaggering down the streets. Researchers have genetically modified bugs to churn out the indigo pigment used to stain denim. The process could be a greener rival to chemical indigo production.
Originally extracted from plants, indigo dye is now made from coal or oil, with potentially toxic by-products. Bacteria have previously been adapted as alternative indigo manufacturers, but a trace by-product renders jeans an unfashionable shade of red.
Biotech indigo starts with a chemical called tryptophan, which bacteria produce naturally. Tryptophan is ideal for conversion to indigo because it already contains the ring-structure at the core of the indigo molecule. A few chemical alterations convert tryptophan into the dye.
Bioindigo E. coli have an enzyme from another microbe engineered into them that converts trytophan into the ring-containing indigo precursor indoxyl; this spontaneously turns into indigo when exposed to air.
Weyler and his team tinkered with their E. coli so that they churned out high levels of the raw material tryptophan. The researchers also inserted a gene that cuts down production of the contaminating red pigment. The efficiency of the process still needs to be improved, however, Crabb concedes.
Before the chemical process was invented, people used plants such as woad and dyers knotweed to make indigo: soaking their leaves in water releases indigos chemical precursors. How these are converted to indigo is still a mystery. Biochemist Philip John of the University of Reading, UK is heading a project to re-introduce indigo- yielding crops into Europe as a natural alternative to chemical synthesis.
Biotech and plant production would both have to be souped-up to feed the worlds obsession with blue jeans: 16,000 tonnes of dye are made annually, almost all of which is used on denim. "Theres no other dye that will give that characteristic colour," explains John, "Its got to be indigo."
HELEN PEARSON | © Nature News Service
Closing the carbon loop
08.12.2016 | University of Pittsburgh
Newly discovered bacteria-binding protein in the intestine
08.12.2016 | University of Gothenburg
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
08.12.2016 | Life Sciences
08.12.2016 | Physics and Astronomy
08.12.2016 | Materials Sciences