Long back I posted about 3D printer and there I placed youtube videos showing that one can make real useful stuff such as a mechanical wrench or a bicycle suitable for riding. But so far 3D printing was limited to non-living physical objects. Now recently Dr Will Wenmiao Shu and his team members at Heriot-Watt University in Edinburgh, Scotland have successfully printed embryonic human stem cells (hESCs). Instead of usual inks for 3D printing, they have use the stem cells floating on a ‘bio ink’ for the printing. Replicating cells in this way carries future promises for organ replacement or regeneration.
Now another remarkable achievement, in a opposite sense (I mean, bio-stuff can be useful for physical non-bio application), has happened in the MIT lab, USA. Prof Timothy K Lu and his coleagues have found an innovative way to use DNA to produce logic gates that perform binary operations (often termed as Booolean Algbera). They have exploited a fancy property of the recombinase enzymes
on E. coli bacteria cells, that allow of prohibit (like ‘on/1’ and ‘off/0’ state of Boolean Algebra) gene transcription on certain conditions. A green fluorescent protein (GFP) has been used
as the output indicator (lighting of the GFP indicates an ‘on’ sate). The work has been published in this month’s Nature Biotechnology issue.