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81.
We have compared the characteristics of nitrate uptake by Aphanothece halophytica grown under non-stress and salt-stress conditions. Both cell types showed essentially similar patterns of nitrate uptake toward ammonium, nitrite, and DL-glyceraldehyde. Although the affinities of nitrate to non-stress cells and salt-stress cells were not significantly different, i.e., Ks = 416 and 450 microM, respectively, the V(max) value for non-stress cells was about twofold of that for salt-stress cells (9.1 vs 5.3 micromol min(-1) mg(-1) Chl). Nitrate uptake by A. halophytica was found to be dependent on Na+. Ammonium inhibited nitrate uptake, and the presence of methionine sulfoximine could not release the inhibition by ammonium. Nitrite appeared to competitively inhibit nitrate uptake with a K(i) value of 84 microM. Both chloride and phosphate anions did not affect nitrate uptake. DL-Glyceraldehyde, an inhibitor of CO2 fixation, caused a reduction in the uptake of nitrate. 相似文献
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A gastrin gene is expressed in both porcine pituitary and antral mucosal tissues. 总被引:6,自引:0,他引:6 下载免费PDF全文
By employing S1 nuclease mapping of total RNA isolated from porcine cerebral cortex, cerebellum, hypothalamus, pituitary, kidney, liver, pancreas, intestine, and antral mucosa, we have investigated gastrin gene expression in these tissues. Our results show that a gastrin gene is expressed only in the antral mucosal and pituitary tissues. Based on the amount of gastrin specific probe protected from S1 nuclease digestion in the presence of a given weight of total RNA, the amount of gastrin mRNA present in pituitary is approximately 330 times lower than in antral mucosa. These findings help establish the tissue distribution of gastrin gene expression. 相似文献
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Janine Schuurman Yvo F Graus Aran F Labrijn Sigrid R Ruuls Paul WHI Parren 《MABS-AUSTIN》2014,6(4):812-819
Open innovation is the new buzz, with initiatives popping up left and right. Here, we give a personal perspective on a very successful, knowledge-driven innovation initiated in an academia- industry alliance, which culminated in technology platforms that enable the generation of therapeutic antibodies with novel properties. To start, we provide a general background on open innovation in the drug development field. 相似文献
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A novel human antibody against human immunodeficiency virus type 1 gp120 is V1, V2, and V3 loop dependent and helps delimit the epitope of the broadly neutralizing antibody immunoglobulin G1 b12 下载免费PDF全文
Zwick MB Kelleher R Jensen R Labrijn AF Wang M Quinnan GV Parren PW Burton DR 《Journal of virology》2003,77(12):6965-6978
The V1/V2 and V3 loops are proximal to the CD4 binding site (CD4bs) of human immunodeficiency virus type 1 (HIV-1) gp120 and undergo conformational change upon CD4 receptor engagement by the HIV-1 envelope spike. Nearly all of the reported monoclonal antibodies (MAbs) against the CD4bs exhibit a very limited capacity to neutralize HIV-1. However, one such human MAb, immunoglobulin G1 (IgG1) b12, is uniquely able to neutralize primary isolates across subtypes with considerable potency. The molecular basis for the anti-HIV-1 activity of b12 is not fully understood but is relevant to vaccine design. Here we describe a novel human MAb, 4KG5, whose binding to monomeric gp120 is moderately enhanced by IgG1 b12. In sharp contrast, 4KG5 binding to gp120 is inhibited by soluble CD4 (sCD4) and by all other (n = 14) anti-CD4bs MAbs tested. 4KG5 is unable to recognize gp120 in which either V1, V2, or V3 has been deleted, and MAbs against the V2 or V3 loops inhibit the binding of 4KG5 to gp120. Moreover, 4KG5 is able to inhibit the binding of the CD4-induced MAbs 17b and X5 in the absence of sCD4, whereas 17b and X5 only weakly inhibit the binding of 4KG5 to gp120. Mutagenesis of gp120 provides further evidence of a discontinuous epitope of 4KG5 that is formed by the V1/V2 loop, the V3 loop, and a portion of the bridging sheet (C4). 4KG5 was isolated as a single-chain Fv from a phage display library constructed from the bone marrow of an HIV-1-seropositive subject (FDA2) whose serum neutralizes HIV-1 across subtypes. Despite its source, we observed no significant neutralization with 4KG5 against the autologous (R2) virus and several other strains of HIV-1. The results suggest a model in which antibody access to the CD4bs on the envelope spike of HIV-1 is restricted by the orientation and/or dynamics of the V1/V2 and V3 loops, and b12 avoids these restrictions. 相似文献
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Anyanee Bunchai Oramas Suttinun Aran H-Kittikun Charongpun Musikavong 《The International Journal of Life Cycle Assessment》2017,22(11):1802-1814
Purpose
The crude palm oil (CPO) extraction is normally done by a wet extraction process, and wastewater treatment of the wet process emits high levels of greenhouse gases (GHGs). A dry process extracts mixed palm oil (MPO) from palm fruit without using water and has no GHG emissions from wastewater treatment. This work is aimed at determining the GHG emissions of a dry process and at evaluating GHG savings on changing from wet to dry process, including land use change (LUC) effects.Methods
Life cycle assessment from cradle to gate was used. The raw material is palm fruits. The dry process includes primary production, oil room, and utilities. MPO is the main product, while palm cake and fine palm residue are co-products sold for animal feed. Case studies were undertaken without and with carbon stocks of firewood and of nitrogen recycling at plantations from fronds. Allocations by mass, economic, and heating values were conducted. The trading of GHG emissions from co-products to GHG emissions from animal feed was assessed. The GHG emissions or savings from direct LUC (dLUC) and from indirect LUC (iLUC) effects and for the change from wet to dry process were determined.Results and discussion
Palm fruit and firewood were the major GHG emission sources. Nitrogen recycling on plantations from fronds significantly affects the GHG emissions. With the carbon stocks, the GHG emissions allocated by energy value were 550 kg CO2 eq/t MPO. The GHG emissions were affected by ?3 to 37% for the change from wet to dry process. When the plantation area was increased by 1 ha and the palm oil extraction was changed from wet to dry process, and the change included dLUC and iLUC, the GHG savings ranged from ?0.94 to 5.08 t CO2 eq/ha year. The iLUC was the main GHG emission source. The GHG saving mostly originated from the change of extraction process and from the dLUC effect. Based on the potential use of biodiesel production from oil palm, during 2015–2036 in Thailand, when the extraction process was changed and dLUC and iLUC effects were included, the saving in GHG emissions was estimated to range from ?35,454 to 274,774 t CO2 eq/year.Conclusions
The change of palm oil extraction process and the LUC effects could minimize the GHG emissions from the palm oil industry. This advantage encourages developing policies that support the dry extraction process and contribute to sustainable developments in palm oil production.90.