Isobutanol Production by Autotrophic Acetogenic Bacteria.

Two different isobutanol synthesis pathways were cloned into and expressed in the two model acetogenic bacteria and . is specialized on using CO + H gas mixtures for growth and depends on sodium ions for ATP generation by a respective ATPase and Rnf system. On the other hand, grows well on syngas (CO + H + CO mixture) and depends on protons for energy conservation.

Identifying and Engineering Bottlenecks of Autotrophic Isobutanol Formation in Recombinant by Systemic Analysis.

(, CLJU) is natively endowed producing acetic acid, 2,3-butandiol, and ethanol consuming gas mixtures of CO, CO, and H (syngas). Here, we present the syngas-based isobutanol formation using harboring the recombinant amplification of the "Ehrlich" pathway that converts intracellular KIV to isobutanol. Autotrophic isobutanol production was studied analyzing two different strains in 3-L gassed and stirred bioreactors.

Electron availability in CO , CO and H mixtures constrains flux distribution, energy management and product formation in Clostridium ljungdahlii.

Acetogens such as Clostridium ljungdahlii can play a crucial role reducing the human CO footprint by converting industrial emissions containing CO , CO and H into valuable products such as organic acids or alcohols. The quantitative understanding of cellular metabolism is a prerequisite to exploit the bacterial endowments and to fine-tune the cells by applying metabolic engineering tools. Studying the three gas mixtures CO  + H , CO and CO + CO  + H (syngas) by continuously gassed batch cultivation experiments and applying flux balance analysis, we identified CO as the preferred carbon and electron source for growth and producing alcohols.

Nuclear RNAs confined to a reticular compartment between chromosome territories.

RNA polymerase II transcripts are confined to nuclear compartments. A detailed analysis of the nuclear topology of RNA from individual genes was performed for transcripts from the marker gene coding for chloramphenicol acetyltransferase, expressed at a high level from the HTLV-1 LTR promoter. The construct was transfected into A293 cells where the RNA was organized as an extensive reticular network.