P-Maltose

Figure 3. Schematic diagram of the hydrogen-bond structure of p-maltose monohydrate (MALTOS11). The anrows indicate infinite chains. Distances and angles are from the neutron diffraction analysis.

Figure 10. Relaxed (adiabatic) conformational energy map for p-maltose as computed by Brady and coworkers.i3 Contours are drawn at 2,4,6, 8, and 10 kcal/mol above the minimum near < ), y = -60°, -40°. The p-maltose structure may be derived from that of p-cellobiose in Fig. 1 by inversion of the stereochemical configuration at Cl.

An ab initio calculation with a minimal basis set of both a- and 0-glucopyranose as well as p-maltose results in the correct prediction of the energetical order of the two glucose anomers as well as the two conformations of p-maltose [80], But the less favored conformer contains an energy which is higher by a factor of approximately 6 compared to the results of the FF300 calculation (cf. below). 

Glycine Glycinate ion Glycylglycine Glycylglycinate L(+)-Lactic acid L(+)-Lactate ion a-Lactose p-Lactose DL-Leudne L-Leucine L-Leucinate ion L-Malic acid L-Malate ion a-Maltose p-Maltose Methanol L-Methionine Oxaloacetic acid Oxaloacetate ion Palmitic acid Pyruvic acid Pyruvate ion 2-Propanol Succinic acid Succinate ion Sucrose dl-Valine L-Valine L-Valine ion L-Valinate ion Water... 

The glycosidic bond to an anomeric carbon can be either a or p. Maltose, the disaccharide obtained by enzyme-catalyzed hydrolysis of starch, consists of two a-n-glucopyranose units joined by a 1- 4-Q-glycoside bond. Cellobiose, the disaccharide obtained by partial hydrolysis of cellulose, consists of two jS-D-glucopyranose units joined by a l->4-/ -glycoside bond. 

Fraction Yield in per cent Color with iodine [ Id Mol. wt. P, % Maltose, % ... 

S. Melberg and K. Rasmussen, Conformations of disaccharides by empirical force field calculations. part 1, P-maltose. Carbohydr. Res., 69 (1979) 27. 

GH 14. The main members of this family are p-amylases, which yield p-maltose from the non-reducing ends of starch. Four maltose molecules are found in the complex of maltose with the holoenzyme from Bacillus cereus, two in tandem in the active site, one in a C-terminal CBM and a fourth in what appears to be an internal CBM. ... 

PHAs containing unsaturated or brominated side chains have been used as substrates for the production of glycoconjugates (derivatives of per-O-acetyl-l-thio-P-maltose-PHAs) via anti-Markovnikov additions. As expected, maltosyl-PHAs showed an enhanced hydrophihcity and hence better solubility and bioavailability (Constantin et al. 1999). 

Hepta-O-acetyl-a-D-lactosyl bromide, H-7 l,2,2",3,3",4",6-H ta-0-acetyl-p-maltose, M-15 l,2,2",3",4",6,6"-H ta-0-acetyl-p-maltose, M-15 l,2, 3,3",4",6,6"-H ta-0-acetyl-p-maltose, M-15 2,2, 3,3",4",6,6"-H ta-0-acetyl-p-maltose, M-15 Hepta- O -acetyl-a-primeveropyranose, X-47 Hepta-O-acetyl-p-primeveroside, X-47 Hepta-O-acetyl-p-rutinose, R-44 2,2, 3,3, 4, 6,6 -Hepta-0-acetyl-l-thio-p-E>-ceIIobiose, T-60 Hepta-O-acetyl-P-turanopyranose, T-201 Hexa-O-acety 1-1,6-anhydro-6-bromomaltose, M-15 Hexa-O-acetyl-a-robinobiosyl bromide, R-28 a-L-/Ar o-4-Hex-4-enopyranuronosyl-D-galacturonic add, H-80 Hyalbiuronic acid N-Ac, H-127... 

The hydrolyses of phenyl a-maltoside and diverse substituted-phenyl a-malto-sides by B. subtilis a-amylase have been examined under conditions that produce only maltose and the corresponding phenols, so that the anomeric configuration of the released disaccharide could be determined. At the pH optimum (5.4) of the enzyme, maltose was released as the P-anomer cf. a previous report although some of the a-anomer was released at high pH values. The action of B. subtilis a-amylase on a- and p-maltose has been studied plots of the initial rate against the substrate concentration gave sigmoidal curves in both cases. ... 

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