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721.
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Yeast (Y) and hyphal (H) cells of Mucor rouxii and Candida albicans were cultivated in liquid media containing different carbon nutrient sources (glucose, fructose, ribose), and their free acyclic polyol and trehalose contents determined using capillary gas liquid chromatography (TMS- and OAc-derivatization). Irrespective of growth form and C-source, the fraction of the water-soluble neutral components of the cellular mass of the cultures — highly homogeneous with regard to the respective cell form produced — contained glycerol, ribitol and arabitol, in addition to trehalose. The polyols contributed 0.5–2% to the biomass of M. rouxii and 1.5–6% to that of C. albicans; the values for trehalose ranged from 0.2–11% in the former and 1–3.5% in the latter species. Mucor contained higher amounts of ribitol and arabitol in H cells and larger quantities of trehalose and glycerol in Y cells. In Candida, too, hyphae always exhibited higher ribitol contents, whereas arabitol attained higher levels in yeasts under almost any conditions — regardless of the type of medium (synthetic vs. complex), stage of culture (early vs. late log-phase) and strain used. Glycerol concentration was not correlated with the growth form; trehalose contents tended to be higher in Y cells. Taking into account the facts that C. albicans and certain Mucor species are agents of opportunistic infections and are invasive mainly in the filamentous form, and that the prospective hosts do not accumulate either of these carbohydrates, the possibility is considered of using trehalose- and polyol-metabolizing enzymes as targets for designing antifungal drugs.  相似文献   
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725.
Membranes of fat globules of cow milk contained 163 μg/100 mg (dry weight) of glycosaminoglycans (expressed as uronic acid); 62.5% of the uronic acids corresponded to hyaluronic acid, the remaining consisted of sulfated glycosaminoglycans (chondroitin-4-(-6) sulfates, and dermatan and heparan sulfates) with different degrees of sulfation.  相似文献   
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Trehalose levels were determined over two 24 hr spans in groups of face fly adults 3-4 days after emergence from the puparium. Face fly pupae were placed in rearing chambers at 27° C in a staggered light-dark regimen, LD 16:8, so that at a given clock hour, samples could be obtained at several different hours after lights on (HALO). Trehalose was determined in hemolymph collected from a puncture in the intersegmental membrane of the abdomen. Treated hemolymph samples were passed through a Bio-Rad Amino S-S disaccharide column and a Waters 410 refractive index detector was used to differentiate among sugars. The circadian acrophase derived by cosinor analysis in hemolymph trehalose (when the values were 25.49 and 26.86μg/μ1 on the first and second days respectively) occurred at -226° (ca 15 HALO) and the bathyphase at 24 HALO. The mesor = 11.82μg/μ1 trehalose, the amplitude = 8.57/μg/μ1 trehalose and the P-value for presence of a rhythm was 0.003. Based on these data, differences between control and test flies in a bioassay of hypertrehalosemic activity would be most easily observed at 0-8 HALO, while exogenous hypotrehalosemic activity would be best assayed at 12-20 HALO.  相似文献   
728.
Hybridization studies have been carried out with Typha angustifolia, T. latifolia, T. shuttleworthii and T. minima. All combinations, except those with T. minima, were successful. The hybrid T. latifolia (♀) × T. angustifolia (♂) has been obtained after 5 attempts involving hundreds of pollinations. The pollen proteins of the parental as well as the F1 generation have been examined by isoelectrofocusing (IEF). The proteins from each species and each hybrid form displayed a distinct and constant pattern. The pollen protein profile thus represents a new, quite easily accessible character by which F1 hybrids between the species studied can be unequivocally identified, whereas the morphological criteria described in the literature to distinguish intermediate forms is insufficient for this purpose.  相似文献   
729.
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