scholarly journals Bacterioplankton Community Structure and Dynamics after Large-Scale Release of Nonindigenous Bacteria as Revealed by Low-Molecular-Weight-RNA Analysis

1993 ◽  
Vol 59 (1) ◽  
pp. 351-351
Keyword(s):  
Molecular Weight ◽  
Community Structure ◽  
Large Scale ◽  
Low Molecular Weight ◽  
Bacterioplankton Community ◽  
Structure And Dynamics ◽  
Rna Analysis

Functional design of glycan-conjugated molecules using a chemoenzymatic approach

2021 ◽  
Author(s):  
Makoto Ogata
Keyword(s):  
Molecular Weight ◽  
Large Scale ◽  
Biological Activities ◽  
Natural Compounds ◽  
Low Molecular Weight ◽  
Functional Design ◽  
Enzymatic Method ◽  
Conjugated Molecules ◽  
Design Synthesis ◽  
And Function

Abstract Carbohydrates play important and diverse roles in the fundamental processes of life. We have established a method for accurately and a large scale synthesis of functional carbohydrates with diverse properties using a unique enzymatic method. Furthermore, various artificial glycan-conjugated molecules have been developed by adding these synthetic carbohydrates to macromolecules and to middle and low molecular weight molecules with different properties. These glycan-conjugated molecules have biological activities comparable to or higher than those of natural compounds, and present unique functions. In this review, several synthetic glycan-conjugated molecules are taken as examples to show design, synthesis and function.

scholarly journals Determination of the Structural Integrity and Stability of Polysialic Acid during Alkaline and Thermal Treatment

Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 165
Author(s):  
Bastian Bartling ◽  
Johanna S. Rehfeld ◽  
Daniel Boßmann ◽  
Ingo de Vries ◽  
Jörg Fohrer ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Large Scale ◽  
Polysialic Acid ◽  
Alkaline Solutions ◽  
Low Molecular Weight ◽  
Outer Cell ◽  
Scale Production ◽  
Thermal Hydrolysis ◽  
E Coli ◽  
Chain Lengths

Polysialic acid (polySia) is a linear homopolymer of varying chain lengths that exists mostly on the outer cell membrane surface of certain bacteria, such as Escherichia coli (E. coli) K1. PolySia, with an average degree of polymerization of 20 (polySia avDP20), possesses material properties that can be used for therapeutic applications to treat inflammatory neurodegenerative diseases. The fermentation of E. coli K1 enables the large-scale production of endogenous long-chain polySia (DP ≈ 130) (LC polySia), from which polySia avDP20 can be manufactured using thermal hydrolysis. To ensure adequate biopharmaceutical quality of the product, the removal of byproducts and contaminants, such as endotoxins, is essential. Recent studies have revealed that the long-term incubation in alkaline sodium hydroxide (NaOH) solutions reduces the endotoxin content down to 3 EU (endotoxin units) per mg, which is in the range of pharmaceutical applications. In this study, we analyzed interferences in the intramolecular structure of polySia caused by harsh NaOH treatment or thermal hydrolysis. Nuclear magnetic resonance (NMR) spectroscopy revealed that neither the incubation in an alkaline solution nor the thermal hydrolysis induced any chemical modification. In addition, HPLC analysis with a preceding 1,2-diamino-4,5-methylenedioxybenzene (DMB) derivatization demonstrated that the alkaline treatment did not induce any hydrolytic effects to reduce the maximum polymer length and that the controlled thermal hydrolysis reduced the maximum chain length effectively, while cost-effective incubation in alkaline solutions had no adverse effects on LC polySia. Therefore, both methods guarantee the production of high-purity, low-molecular-weight polySia without alterations in the structure, which is a prerequisite for the submission of a marketing authorization application as a medicinal product. However, a specific synthesis of low-molecular-weight polySia with defined chain lengths is only possible to a limited extent.

scholarly journals Structure and Dynamics of Bimodal Colloidal Dispersions in a Low-Molecular-Weight Polymer Solution

Langmuir ◽  
2017 ◽  
Vol 33 (11) ◽  
pp. 2817-2828 ◽  
Author(s):  
Fan Zhang ◽  
Andrew J. Allen ◽  
Lyle E. Levine ◽  
De-Hao Tsai ◽  
Jan Ilavsky
Keyword(s):  
Molecular Weight ◽  
Polymer Solution ◽  
Colloidal Dispersions ◽  
Low Molecular Weight ◽  
Molecular Weight Polymer ◽  
Structure And Dynamics

scholarly journals Low molecular weight organic acids in aerosol particles from Rondônia, Brazil, during the biomass-burning, transition and wet periods

2004 ◽  
Vol 4 (5) ◽  
pp. 6867-6907 ◽  
Author(s):  
A. H. Falkovich ◽  
E. R. Graber ◽  
G. Schkolnik ◽  
Y. Rudich ◽  
W. Maenhaut ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Organic Acids ◽  
Biomass Burning ◽  
Large Scale ◽  
Inorganic Compounds ◽  
Fine Fraction ◽  
Dicarboxylic Acids ◽  
Water Soluble ◽  
Low Molecular Weight ◽  
Ionic Mass

Abstract. Particles from biomass burning and regional haze were sampled in Rondônia, Brazil, during dry, transition and wet periods from September to November 2002, as part of the LBA-SMOCC (Large-Scale Biosphere-Atmosphere Experiment in Amazonia – Smoke, Aerosols, Clouds, Rainfall, and Climate) field campaign. Water soluble organic and inorganic compounds in bulk (High Volume and Stacked Filter Unit sampler) and size-resolved (Micro Orifice Uniform Deposit Impactor – MOUDI) smoke samples were determined by ion chromatography. It was found that low molecular weight polar organic acids account for a significant fraction of the water soluble organic carbon (WSOC) in biomass burning aerosols (C2-C6 dicarboxylic acids reached up to 3.7% and one-ring aromatic acids reached up to 2% of fine fraction WSOC during burning period). Short dicarboxylic (C2-C6) acids are dominated by oxalic acid followed by malonic and succinic acids. The largest ionic species is ammonium sulfate (60–70% of ionic mass). It was found that most of the ionic mass is concentrated in submicrometer-sized particles. Based on the size distribution and correlations with K+, a known biomass burning tracer, it is suggested that many of the organic acids are directly emitted by vegetation fires. It is concluded that the dicarboxylic acids are mostly confined to the particulate phase, and no evidence for semi-volatile behavior was observed. Finally, it is shown that the distribution of water soluble species shifts to larger aerosols sizes as the aerosol population ages and mixes with other aerosol types in the atmosphere.

Large-scale isolation of fraction 1 leaf protein (18S) from lucerne (Medicago sativa L)

1976 ◽  
Vol 86 (3) ◽  
pp. 495-501 ◽  
Author(s):  
W. T. Jones ◽  
J. L. Mangan
Keyword(s):  
Molecular Weight ◽  
Medicago Sativa ◽  
Ammonium Sulphate ◽  
Large Scale ◽  
Gel Filtration ◽  
Low Molecular Weight ◽  
Fraction 1 Protein ◽  
Ammonium Sulphate Fractionation ◽  
Medicago Sativa L ◽  
Soluble State

SummaryFraction 1 protein (18S) can be isolated in large quantities (order 100 g) in a soluble state by heating lucerne juice, adjusted to pH 6·7 to 6·9, from a Pirie extractor to 63 °C for 10 min. Low speed oentrifugation (2500 g) removed coagulated chloroplast fragments and most of the heat-denatured Fraction 2 proteins. Fraction 1 (18S) protein (> 95% pure) was purified from low molecular weight materials (sugars, phenolics etc.) by ammonium sulphate fractionation and gel filtration on Sephadex G-75 gels.

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