Utilization of Molasses Sugar for Lactic Acid Production by Lactobacillus delbrueckii subsp. delbrueckii Mutant Uc-3 in Batch Fermentation▿

Efficient lactic acid production from cane sugar molasses by Lactobacillus delbrueckii mutant Uc-3 in batch fermentation process is demonstrated. Lactic acid fermentation using molasses was not significantly affected by yeast extract concentrations. The final lactic acid concentration increased with increases of molasses sugar concentrations up to 190 g/liter. The maximum lactic acid concentration of 166 g/liter was obtained at a molasses sugar concentration of 190 g/liter with a productivity of 4.15 g/liter/h. Such a high concentration of lactic acid with high productivity from molasses has not been reported previously, and hence mutant Uc-3 could be a potential candidate for economical production of lactic acid from molasses at a commercial scale

Viperin binds STING and enhances the type-I interferon response following dsDNA detection

First published: 01 November 2020Viperin is an interferon-inducible protein that is pivotal for eliciting an effective immune response against an array of diverse viral pathogens. Here we describe a mechanism of viperin's broad antiviral activity by demonstrating the protein's ability to synergistically enhance the innate immune dsDNA signalling pathway to limit viral infection. Viperin co-localised with the key signalling molecules of the innate immune dsDNA sensing pathway, STING and TBK1; binding directly to STING and inducing enhanced K63-linked polyubiquitination of TBK1. Subsequent analysis identified viperin's necessity to bind the cytosolic iron-sulphur assembly component 2A, to prolong its enhancement of the type-I interferon response to aberrant dsDNA. Here we show that viperin facilitates the formation of a signalling enhanceosome, to coordinate efficient signal transduction following activation of the dsDNA signalling pathway; which results in an enhanced antiviral state. We also provide evidence for viperin's radical SAM enzymatic activity to self-limit its immunomodulatory functions. These data further define viperin's role as a positive regulator of innate immune signalling, offering a mechanism of viperin's broad antiviral capacity.Keaton M Crosse, Ebony A Monson, Arti B Dumbrepatil, Monique Smith, Yeu-Yang Tseng, Kylie H Van der Hoe

Tetrameric architecture of an active phenol-bound form of the AAA⁺ transcriptional regulator DmpR

The Pseudomonas putida phenol-responsive regulator DmpR is a bacterial enhancer binding protein (bEBP) from the AAA+ ATPase family. Even though it was discovered more than two decades ago and has been widely used for aromatic hydrocarbon sensing, the activation mechanism of DmpR has remained elusive. Here, we show that phenol-bound DmpR forms a tetramer composed of two head-to-head dimers in a head-to-tail arrangement. The DmpR-phenol complex exhibits altered conformations within the C-termini of the sensory domains and shows an asymmetric orientation and angle in its coiled-coil linkers. The structural changes within the phenol binding sites and the downstream ATPase domains suggest that the effector binding signal is propagated through the coiled-coil helixes. The tetrameric DmpR-phenol complex interacts with the σ54 subunit of RNA polymerase in presence of an ATP analogue, indicating that DmpR-like bEBPs tetramers utilize a mechanistic mode distinct from that of hexameric AAA+ ATPases to activate σ54-dependent transcription.</p

Tetrameric architecture of an active phenol-bound form of the AAA(+) transcriptional regulator DmpR

The Pseudomonas putida phenol-responsive regulator DmpR is a bacterial enhancer binding protein (bEBP) from the AAA+ ATPase family. Even though it was discovered more than two decades ago and has been widely used for aromatic hydrocarbon sensing, the activation mechanism of DmpR has remained elusive. Here, we show that phenol-bound DmpR forms a tetramer composed of two head-to-head dimers in a head-to-tail arrangement. The DmpR-phenol complex exhibits altered conformations within the C-termini of the sensory domains and shows an asymmetric orientation and angle in its coiled-coil linkers. The structural changes within the phenol binding sites and the downstream ATPase domains suggest that the effector binding signal is propagated through the coiled-coil helixes. The tetrameric DmpR-phenol complex interacts with the σ54 subunit of RNA polymerase in presence of an ATP analogue, indicating that DmpR-like bEBPs tetramers utilize a mechanistic mode distinct from that of hexameric AAA+ ATPases to activate σ54-dependent transcription

Tetrameric architecture of an active phenol-bound form of the AAA⁺ transcriptional regulator DmpR

The Pseudomonas putida phenol-responsive regulator DmpR is a bacterial enhancer binding protein (bEBP) from the AAA+ ATPase family. Even though it was discovered more than two decades ago and has been widely used for aromatic hydrocarbon sensing, the activation mechanism of DmpR has remained elusive. Here, we show that phenol-bound DmpR forms a tetramer composed of two head-to-head dimers in a head-to-tail arrangement. The DmpR-phenol complex exhibits altered conformations within the C-termini of the sensory domains and shows an asymmetric orientation and angle in its coiled-coil linkers. The structural changes within the phenol binding sites and the downstream ATPase domains suggest that the effector binding signal is propagated through the coiled-coil helixes. The tetrameric DmpR-phenol complex interacts with the σ54 subunit of RNA polymerase in presence of an ATP analogue, indicating that DmpR-like bEBPs tetramers utilize a mechanistic mode distinct from that of hexameric AAA+ ATPases to activate σ54-dependent transcription.BN/Chirlmin Joo La

Viperin binds STING and enhances the type- I interferon response following dsDNA detection

Viperin is an interferon- inducible protein that is pivotal for eliciting an effective immune response against an array of diverse viral pathogens. Here we describe a mechanism of viperin- s broad antiviral activity by demonstrating the protein- s ability to synergistically enhance the innate immune dsDNA signaling pathway to limit viral infection. Viperin co- localized with the key signaling molecules of the innate immune dsDNA sensing pathway, STING and TBK1; binding directly to STING and inducing enhanced K63- linked polyubiquitination of TBK1. Subsequent analysis identified viperin- s necessity to bind the cytosolic iron- sulfur assembly component 2A, to prolong its enhancement of the type- I interferon response to aberrant dsDNA. Here we show that viperin facilitates the formation of a signaling enhanceosome, to coordinate efficient signal transduction following activation of the dsDNA signaling pathway, which results in an enhanced antiviral state. We also provide evidence for viperin- s radical SAM enzymatic activity to self- limit its immunomodulatory functions. These data further define viperin- s role as a positive regulator of innate immune signaling, offering a mechanism of viperin- s broad antiviral capacity.Here we show for the first time that the antiviral protein viperin is able to enhance the type- I interferon response to dsDNA. Viperin directly binds STING to facilitate effective activation of TBK1 through K63 polyubiquitination, resulting in an enhanced antiviral response. This process is driven by an interaction between viperin and CIA2A, demonstrating a novel role for iron- sulfur cluster assembly proteins in the regulation of innate immune signaling.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/167491/1/imcb12420.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/167491/2/imcb12420_am.pd