Molecular weight native

Highly ordered crystalline cellulose has a density as high as 1.63 g cm whereas highly disordered amorphous cellulose has a density as low as 1.47 g cm 3. High-molecular-weight native cellulose, which is insoluble in 17,5% aqueous sodium hydroxide solution, is called alpha cellulose. The fraction that is soluble in 17.5% sodium hydroxide solution but insoluble in 8% solution, is called beta cellulose, and that which is soluble in 8% sodium hydroxide solution is called gamma cellulose. 

To express the results in terms of a few distinctly linear stages is a simplification. We have reviewed a number of factors that can influence the ease of chain scissioning. A point that we have not discussed, however, is the fact that several researchers (31, 32) have suggested that high-molecular-weight native celluloses may have a significant crystallite or chain-dislocation unit of the order of DP = 500. The overall rate must certainly represent transitions between the predominating influence of one or another of the factors noted. 

The shapes of the inhibition curves in Fig. 1A, B, and E are atypical since IgA myeloma proteins are mixtures of monomers and polymers. Using a lower molecular weight dextran N-150N, rather than the higher molecular weight native B512, typical inhibition curves as shown in Fig. 1C were obtained. If the myeloma antidextran was separated into monomer and polymer portions, the usual inhibition curves could be obtained (Cisar et al., 1974). 

Lectin Molecular weight Native Subunit KDa KDa Subunit structure... 

A new protein of unknown structure has been purified. Gel filtration chromatography reveals that the native protein has a molecular weight of 240,000. Chromatography in the presence of 6 M guanidine hydrochloride yields only a peak for a protein of M, 60,000. Chromatography in the presence of 6 M guanidine hydrochloride and 10 mM /3-mercaptoethanol yields peaks for proteins of M, 34,000 and 26,000. Explain what can be determined about the structure of this protein from these data. 

The native luciferase having a molecular weight of 106,000 probably consists of two units of the functional 19 kDa protein and two units of the 35 kDa protein. The value of A28o,icm for a solution containing 1 mg/ml of the native luciferase is calculated to be about 0.9 from the inferred amino acid sequence. The function of the 35 kDa protein remains unclear, although it might have a role in the stabilization of the 19 kDa protein. 

A number of different low molecular weight compounds are known to stablize proteins in their native conformation and, therefore, may be effective in correcting of protein folding abnormalities in vivo. Relevant compounds are iV-acetyl-L-lysine, L-camitine, taurine, betaine, ectoine, and hydroxy-ectoine [4]. Some of these chemical chaperones and pharmacological chaperones are already used in clinical trials to combat protein folding diseases, such as cystic fibrosis. 

Sensitivities achieved in f.a.b. analysis are both operator- and sample-dependent. Experienced mass spectrometrists working with well purified samples use between 0.1 and 5 jig of sample when analyzing derivatives, and between 1 and 10 (ig when analyzing native compounds. The higher the molecular weight, the greater the quantity of sample needed. 

ATPase and specific modification of root cell membrane permeability directly mediated by low-molecular-weight (<5000 Da) fulvic acid-like compounds deriving from native soil organic matter (54-56) (see also Chap. 5). 

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