The permeability function the cell wall of gram-negative bacteria such as Salmoenlla was investigated by producing cells with an expanded periplasmic volume, and incubating them with radioactive non-utilizable oligo- and polysaccharides or polyethylene glycols. To quantitative the extent of penetration of these hydrophilic compounds into the periplasm, the radioactivity of the cell pellet was determined after centrifugation. We found that only di- and trisaccharides could fully diffuse into the periplasm, whereas higher-molecular-weight saccharides were nonpenetrable. In addition, low-molecular-weight polyethylene glycols rapidly diffused across the cell wall. Kinetics experiments also showed that both sucrose and raffinose in the periplasm exchanged rapidly with sugars in the medium, even at 0 degrees C. These results suggest that the cell wall acts as a molecular sieve, with an exclusion limit near 550 to 650 daltons for saccharides. We also suggest that the diffusion of these hydrophilic compounds most likely occurs through water-filled pores present in the cell wall of gram-negative bacteria.

Outer membrane of gram-negative bacteria. XII. Molecular-sieving function of cell wall.

Isolation and partial characterization of an extracellular glucansucrase from Leuconostoc mesenteroides NRRL B-1355 that synthesizes an alternating (1→6), (1→3)-α-d-glucan

https://febs.onlinelibrary.wiley.com/doi/pdf/10.1016/0014-5793%2875%2980806-4

A new substrate for investigating the specificity of β-glucan hydrolases

SUMMARY
The non-structural carbohydrate content of individual leaf bases of onion bulbs was determined, and confirmed the presence of glucose, fructose, sucrose and a series of fructans as the only components. The fructans decreased in concentration with increasing molecular weight and those with a DP (degree of polymerization) of up to 10 were estimated. Total fructan concentration decreased from the youngest to the oldest leaf bases of the bulb, while fructose levels increased and glucose and sucrose levels tended to remain constant.

https://nph.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-8137.1978.tb01600.x

Götz Trenel

Papers

Quantitative chromatography of homologous glucose oligomers and other saccharides using polyacrylamide gel

Gel permeation chromatography of maltooligosaccharides at different temperatures