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Cryptic invertebrate communities in coral rubble and sand from Hanauma Bay, a Marine Life Conservation District, were analyzed. Substratum samples were collected from the shallow bench and sand channels next to the beach and the cryptofauna were examined. Sand from the shallows (0.6 m deep) is frequently trampled by beach users and has a depauperate community dominated by a polychaete (Saccocirrus alanhongi) and a variety of nematodes (mean no. taxa = 12, mean no. individuals = 1,143 (0.1 m–2), but sand collected 25 m seaward from below trampling depths (3 m). showed significantly greater diversity (mean no. taxa = 46, mean no. individuals = 6,448 (0.1 m–2). Coralline rubble from 0.5 m depth was acid dissolved to extract the cryptofauna that was trapped on 0.5 and 0.25 mm sieves. In total, 102 taxa and 10,673 individual invertebrates (0.1 m–2) were found. Rubble collected from areas used by waders had a greater diversity than sand habitats. This substratum provides a greater variety of microhabitats and protection from trampling for endolithic fauna than sand. Waders may actively avoid rubble because of the discomfort from walking on this hard, uneven substratum. We found that despite enforced protective measures, i.e., stopping fishing and collecting of marine life, banning fish feeding, and limiting the number of visitors, disturbance by human trampling on shallow sands still reduces the species richness in these areas. Cryptic biota below wading depths, and from adjacent coral rubble on sand, are not similarly affected. These results are similar to those from another heavily used beach on Oahu and cryptofauna ecology may be useful to adopt as a management option for Marine Preserves in other locations. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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A 1,3-rß-glucanase purified from rice grain is a 33kDa monomer with a pI of  相似文献   
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The ethyl carbamate concentration of commercial ume liqueur products was studied, and a method of reducing it was examined from the viewpoint of antioxidation. The average ethyl carbamate concentration across 38 ume liqueur products was 0.12 mg/l (0.02-0.33 mg/l). When potassium metabisulfite was added to a concentration of 0-1,000 ppm during production, the generation of ethyl carbamate was reduced in a concentration-dependent manner, but when the amount of potassium metabisulfite added was below the maximum level allowed under the Japanese Food Sanitation Act, the reduction was only 27%. When ume liqueurs were produced under deoxygenated conditions created using an oxygen absorber, the ethyl carbamate concentration was reduced by up to 47% as compared with the control group, probably due mainly to a reduction in free hydrogen cyanide. When ume liqueur was produced in an oxygen atmosphere, the ethyl carbamate concentration increased by up to 50% as compared with the control group. Thus, oxygen may be involved in the generation of ethyl carbamate in ume liqueur production.  相似文献   
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A glycosylation island is a genetic region required for glycosylation. The glycosylation island of flagellin in Pseudomonas syringae pv. tabaci 6605 consists of three orfs: orf1, orf2 and orf3. Orf1 and orf2 encode putative glycosyltransferases, and their deletion mutants, Deltaorf1 and Deltaorf2, exhibit deficient flagellin glycosylation or produce partially glycosylated flagellin respectively. Digestion of glycosylated flagellin from wild-type bacteria and non-glycosylated flagellin from Deltaorf1 mutant using aspartic N-peptidase and subsequent HPLC analysis revealed candidate glycosylated amino acids. By generation of site-directed Ser/Ala-substituted mutants, all glycosylated amino acid residues were identified at positions 143, 164, 176, 183, 193 and 201. Matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry (MS) analysis revealed that each glycan was about 540 Da. While all glycosylation-defective mutants retained swimming ability, swarming ability was reduced in the Deltaorf1, Deltaorf2 and Ser/Ala-substituted mutants. All glycosylation mutants were also found to be impaired in the ability to adhere to a polystyrene surface and in the ability to cause disease in tobacco. Based on the predicted tertiary structure of flagellin, S176 and S183 are expected to be located on most external surface of the flagellum. Thus the effect of Ala-substitution of these serines is stronger than that of other serines. These results suggest that glycosylation of flagellin in P. syringae pv. tabaci 6605 is required for bacterial virulence. It is also possible that glycosylation of flagellin may mask elicitor function of flagellin molecule.  相似文献   
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Two ent-18-acetoxy-6-oxomanoyl oxides, epimers at C-13, have been prepared from ent-6alpha,8alpha,18-trihydroxylabda-13(16),14-diene (andalusol), isolated from Sideritis foetens, by means of several chemical pathways and a regioselective acylation with Candida cylindracea lipase (CCL). Biotransformation of these 13-epimeric ent-manoyl oxides by Fusarium moniliforme and Neurospora crassa produced mainly ent-1beta- or ent-11alpha-hydroxylations, as well as their deacetylated derivatives, in both epimers. In addition, with the 13-epi substrate N. crassa originated other minor hydroxylations by the ent-alpha face at C-1 or at C-12, whereas an ent-11beta-hydroxyl group, probably originated by reduction of an 11-oxo derivative also isolated, was achieved with the 13-normal substrate.  相似文献   
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The regulation of abscisic acid (ABA) biosynthesis is essential for plant responses to drought stress. In this study, we examined the tissue-specific localization of ABA biosynthetic enzymes in turgid and dehydrated Arabidopsis (Arabidopsis thaliana) plants using specific antibodies against 9-cis-epoxycarotenoid dioxygenase 3 (AtNCED3), AtABA2, and Arabidopsis aldehyde oxidase 3 (AAO3). Immunohistochemical analysis revealed that in turgid plants, AtABA2 and AAO3 proteins were localized in vascular parenchyma cells most abundantly at the boundary between xylem and phloem bundles, but the AtNCED3 protein was undetectable in these tissues. In water-stressed plants, AtNCED3 was detected exclusively in the vascular parenchyma cells together with AtABA2 and AAO3. In situ hybridization using the antisense probe for AtNCED3 showed that the drought-induced expression of AtNCED3 was also restricted to the vascular tissues. Expression analysis of laser-microdissected cells revealed that, among nine drought-inducible genes examined, the early induction of most genes was spatially restricted to vascular cells at 1 h and then some spread to mesophyll cells at 3 h. The spatial constraint of AtNCED3 expression in vascular tissues provides a novel insight into plant systemic response to drought stresses.  相似文献   
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