Combining metabolic engineering and biocompatible chemistry for high-yield production of homo-diacetyl and homo-(S,S)-2,3-butanediol

Liu, J.,Chan, S.H.J.,Brock-Nannestad, T.,Chen, J.,Lee, S.Y.,Solem, C.,Jensen, P.R. Academic Press 2016 Metabolic engineering Vol.36 No.-

Biocompatible chemistry is gaining increasing attention because of its potential within biotechnology for expanding the repertoire of biological transformations carried out by enzymes. Here we demonstrate how biocompatible chemistry can be used for synthesizing valuable compounds as well as for linking metabolic pathways to achieve redox balance and rescued growth. By comprehensive rerouting of metabolism, activation of respiration, and finally metal ion catalysis, we successfully managed to convert the homolactic bacterium Lactococcus lactis into a homo-diacetyl producer with high titer (95mM or 8.2g/L) and high yield (87% of the theoretical maximum). Subsequently, the pathway was extended to (S,S)-2,3-butanediol (S-BDO) through efficiently linking two metabolic pathways via chemical catalysis. This resulted in efficient homo-S-BDO production with a titer of 74mM (6.7g/L) S-BDO and a yield of 82%. The diacetyl and S-BDO production rates and yields obtained are the highest ever reported, demonstrating the promising combination of metabolic engineering and biocompatible chemistry as well as the great potential of L. lactis as a new production platform.

Sporadic Early-Onset Diffuse Gastric Cancers Have High Frequency of Somatic CDH1 Alterations, but Low Frequency of Somatic RHOA Mutations Compared With Late-Onset Cancers

Cho, S.Y.,Park, J.W.,Liu, Y.,Park, Y.S.,Kim, J.H.,Yang, H.,Um, H.,Ko, W.R.,Lee, B.I.,Kwon, S.Y.,Ryu, S.W.,Kwon, C.H.,Park, D.Y.,Lee, J.H.,Lee, S.I.,Song, K.S.,Hur, H.,Han, S.U.,Chang, H.,Kim, S.J.,Kim Elsevier North Holland [etc.] 2017 Gastroenterology Vol.153 No.2

<P>BACKGROUND & AIMS: Early-onset gastric cancer, which develops in patients younger than most gastric cancers, is usually detected at advanced stages, has diffuse histologic features, and occurs more frequently in women. We investigated somatic genomic alterations associated with the unique characteristics of sporadic diffuse gastric cancers (DGCs) from younger patients. METHODS: We conducted whole exome and RNA sequence analyses of 80 resected DGC samples from patients 45 years old or younger in Korea. Patients with pathogenic germline mutations in CDH1, TP53, and ATM were excluded from the onset of this analysis, given our focus on somatic alterations. We used MutSig2CV to evaluate the significance of mutated genes. We recruited 29 additional early-onset Korean DGC samples and performed SNP6.0 array and targeted sequencing analyses of these 109 early-onset DGC samples (54.1% female, median age, 38 years). We compared the SNP6.0 array and targeted sequencing data of the 109 early-onset DGC samples with those from diffuse-type stomach tumor samples collected from 115 patients in Korea who were 46 years or older (late onset) at the time of diagnosis (controls; 29.6% female, median age, 67 years). We compared patient survival times among tumors from different subgroups and with different somatic mutations. We performed gene silencing of RHOA or CDH1 in DGC cells with small interfering RNAs for cell-based assays. RESULTS: We identified somatic mutations in the following genes in a significant number of early-onset DGCs: the cadherin 1 gene (CDH1), TP53, ARID1A, KRAS, PIK3CA, ERBB3, TGFBR1, FBXW7, RHOA, and MAP2K1. None of 109 early-onset DGC cases had pathogenic germline CDH1 mutations. A higher proportion of early-onset DGCs had mutations in CDH1 (42.2%) or TGFBR1 (7.3%) compared with control DGCs (17.4% and 0.9%, respectively) (P<.001 and P=.014 for CDH1 and TGFBR1, respectively). In contrast, a smaller proportion of early-onset DGCs contained mutations in RHOA (9.2%) than control DGCs (19.1%) (P=.033). Late-onset DGCs in The Cancer Genome Atlas also contained less frequent mutations in CDH1 and TGFBR1 and more frequent RHOA mutations, compared with early-onset DGCs. Early-onset DGCs from women contained significantly more mutations in CDH1 or TGFBR1 than early-onset DGCs from men. CDH1 alterations, but not RHOA mutations, were associated with shorter survival times in patients with early-onset DGCs (hazard ratio, 3.4; 95% confidence interval, 1.5 - 7.7). RHOA activity was reduced by an R5W substitution-the RHOA mutation most frequently detected in early-onset DGCs. Silencing of CDH1, but not RHOA, increased migratory activity of DGC cells. CONCLUSIONS: In an integrative genomic analysis, we found higher proportions of early-onset DGCs to contain somatic mutations in CDH1 or TGFBR1 compared with late-onset DGCs. However, a smaller proportion of early-onset DGCs contained somatic mutations in RHOA than late-onset DGCs. CDH1 alterations, but not RHOA mutations, were associated with shorter survival times of patients, which might account for the aggressive clinical course of early-onset gastric cancer. Female predominance in early-onset gastric cancer may be related to relatively high rates of somatic CDH1 and TGFBR1 mutations in this population.</P>

<i>K</i>-mixing in the doubly mid-shell nuclide ¹⁷⁰Dy and the role of vibrational degeneracy

Sö,derströ,m, P.-A.,Walker, P.M.,Wu, J.,Liu, H.L.,Regan, P.H.,Watanabe, H.,Doornenbal, P.,Korkulu, Z.,Lee, P.,Liu, J.J.,Lorusso, G.,Nishimura, S.,Phong, V.H.,Sumikama, T.,Xu, F.R.,Yagi, A.,Zha North-Holland Pub. Co 2016 Physics letters. Section B Vol.762 No.-

<P><B>Abstract</B></P> <P>A detailed study of the structure of the doubly mid-shell nucleus Dy 104 1 66 170 has been carried out, following isomeric and <I>β</I> decay. We have measured the yrast band up to the spin-parity <SUP> J π </SUP> = <SUP> 6 + </SUP> state, the K = 2 <I>γ</I>-vibration band up to the <SUP> 5 + </SUP> state, a low-lying negative-parity band based on a <SUP> 2 − </SUP> state that could be a candidate for the lowest energy octupole vibration state within this nucleus, and a candidate for the <SUP> K π </SUP> = <SUP> 6 + </SUP> two quasi-particle isomer. This state was determined to have an excitation energy of 1643.91(23) keV and a half life of 0.99(4) μs, with a reduced hindrance for its decay to the ground-state band an order of magnitude lower than predicted by <SUB> N p </SUB> <SUB> N n </SUB> systematics. This is interpreted as being due to <I>γ</I>-vibrational mixing from a near degeneracy of the isomer and the <SUP> 6 + </SUP> state of the <I>γ</I> band. Furthermore, the parent nucleus <SUP>170</SUP>Tb has been determined to have a half-life of 0.91 ( − 13 + 18 ) s with a possible spin-parity of <SUP> 2 − </SUP> .</P>

High Frequency Genetic Transformation and Plant Regeneration Using Agrobacterium tumefaciens via Somatic Embryogenesis of Codonopsis lanceolata

Choi, P. S 한국식물조직배양학회 1996 식물생명공학회지 Vol.23 No.4

Selection and Isoenzyme Analysis of Plant Cell Lines for High Yields of Superoxide Dismutase

You, S. H 한국식물조직배양학회 1996 식물생명공학회지 Vol.23 No.2

The Magnetoresistance in Iron-based Superconductors

B. Lv,R. B. Xie,S. L. Liu,G. J. Wu,H. M. Shao,X. S. Wu 한국자기학회 2011 Journal of Magnetics Vol.16 No.2

The phase transition of vortex matter from solid to liquid was studied in iron-based superconductors. Based on the traditional vortex glass theory, we have examined the magnetoresistivity data of iron-based superconductors using our extended thermal activation model: ρ(B,T) = ρ((T-Tg(B))/(Tc(0)-Tg(B)))<SUP>v(z-1)</SUP>. We predict that the magnetic field-dependent area S + S? which integrates ρ with T is proportional to B<SUP>β</SUP>, where β is the vortex glass transition exponent. From our calculation, the vortex glass transition exponent is 0.33, close to the exponent of area S?+ S is 0.31 in SmO0.9F0.1FeAs; the exponent of area S is 0.63, which is close to the irreversibility line exponent 2/3. Both of the results show the validity of our model. In addition, our model is shown to be effective in describing irreversibility behavior in layered superconductors.

Magnetically separable sulfur-doped SnFe₂O₄/graphene nanohybrids for effective photocatalytic purification of wastewater under visible light

Jia, Y.,Wu, C.,Lee, B.W.,Liu, C.,Kang, S.,Lee, T.,Park, Y.C.,Yoo, R.,Lee, W. Elsevier Scientific Pub. Co 2017 Journal of hazardous materials Vol.338 No.-

In this report, magnetically recoverable sulfur-doped SnFe<SUB>2</SUB>O<SUB>4</SUB>/graphene (S-SFO/GR) nanohybrids have been successfully developed via a facile solvothermal method. The characterizations on the structural, morphology, and optical properties of the nanohybrids indicate that S-SFO particles are successfully embedded on the GR nanosheets. The photocatalytic activity has been evaluated by photocatalytic degradation of chlorotetracycline under visible light irradiation. Among the composites with various mass ratios, the quasi-first-order rate constant of the nanohybrids formed with 9wt% S in SFO and 15wt% GR (9S-SFO/GR-15) can reach as high as 1.83min<SUP>-1</SUP>, which is much higher than that of SFO (0.68min<SUP>-1</SUP>) and SFO/GR (0.91min<SUP>-1</SUP>), confirming the important role of S and GR for the photocatalytic process. The combination of the three components of S, SFO, and GR has enhanced the visible light absorption capability and inhibited the recombination of photogenerated electron-hole. The 9S-SFO/GR-15 nanohybrids can be recovered easily by a magnet and reused for five times with remained photocatalytic efficiency about 70%. A possible catalytic mechanism explaining the efficient photocatalytic performances of the prepared nanohybrids has been proposed.

Somatic Embryogenesis and Plant Regeneration in Cell Suspension Cultures of Pepper

Jeong, W. J 한국식물조직배양학회 1996 식물생명공학회지 Vol.23 No.4

Evaluation of VIIRS, GOCI, and MODIS Collection 6 AOD retrievals against ground sunphotometer observations over East Asia

Xiao, Q.,Zhang, H.,Choi, M.,Li, S.,Kondragunta, S.,Kim, J.,Holben, B.,Levy, R. C.,Liu, Y. Copernicus GmbH 2016 Atmospheric Chemistry and Physics Vol.16 No.3

<P>Abstract. Persistent high aerosol loadings together with extremely high population densities have raised serious air quality and public health concerns in many urban centers in East Asia. However, ground-based air quality monitoring is relatively limited in this area. Recently, satellite-retrieved Aerosol Optical Depth (AOD) at high resolution has become a powerful tool to characterize aerosol patterns in space and time. Using ground AOD observations from the Aerosol Robotic Network (AERONET) and the Distributed Regional Aerosol Gridded Observation Networks (DRAGON)-Asia Campaign, as well as from handheld sunphotometers, we evaluated emerging aerosol products from the Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the Suomi National Polar-orbiting Partnership (S-NPP), the Geostationary Ocean Color Imager (GOCI) aboard the Communication, Ocean, and Meteorology Satellite (COMS), and Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) (Collection 6) in East Asia in 2012 and 2013. In the case study in Beijing, when compared with AOD observations from handheld sunphotometers, 51 % of VIIRS Environmental Data Record (EDR) AOD, 37 % of GOCI AOD, 33 % of VIIRS Intermediate Product (IP) AOD, 26 % of Terra MODIS C6 3 km AOD, and 16 % of Aqua MODIS C6 3 km AOD fell within the reference expected error (EE) envelope (±0.05 ± 0.15 AOD). Comparing against AERONET AOD over the Japan-South Korea region, 64 % of EDR, 37 % of IP, 61 % of GOCI, 39 % of Terra MODIS, and 56 % of Aqua MODIS C6 3 km AOD fell within the EE. In general, satellite aerosol products performed better in tracking the day-to-day variability than tracking the spatial variability at high resolutions. The VIIRS EDR and GOCI products provided the most accurate AOD retrievals, while VIIRS IP and MODIS C6 3 km products had positive biases. </P>

Genetic Diversity and Origin of Chinese Domestic Goats Revealed by Complete mtDNA D-loop Sequence Variation

Liu, R.Y.,Lei, C.Z.,Liu, S.H.,Yang, G.S. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.2

China has numerous native domestic goat breeds, but so far there has been no extensive study on genetic diversity, population demographic history, and origin of Chinese goats. To determine the origin and genetic diversity of Chinese goats, we analyzed the complete mtDNA D-loop sequences of 183 goats from 13 breeds. The haplotype diversity value found in each breed ranged from 0.9333 to 1.0000. The nucleotide diversity value ranged from 0.006337 to 0.025194. Our results showed that there were four mtDNA lineages (A, B, C and D), in which lineage A was predominant, lineage B was moderate, and lineages C and D were at low frequencies. Lineages C and D were observed only in the Tibetan breed. The results revealed multiple maternal origins of Chinese domestic goats. There was weaker geographical structuring in the 13 Chinese goat populations, which suggested that there existed high gene flow among goat populations caused by the extensive transportation of goats in the course of history.