Characterization of 13 newly isolated strains of anaerobic, cellulolytic, thermophilic bacteria

Characteristics of 13 newly isolated thermophilic, anaerobic, and cellulolytic strains were compared with previously described strains of Clostridium thermocellum: ATCC 27405 and JW20 (ATCC 31549). Colony morphology, antibiotic sensitivity, fermentation end-products, and cellulose degradation were documented. All 13 strains were sensitive to erythromycin (5 μg/ml) and chloramphenicol (25 μg/ml), and all strains but one were sensitive to kanamycin (20 μg/ml). Polymerase chain reaction (PCR) amplification using primers based on gene sequences from C. thermocellum ATCC 27405 was successful for all 13 strains in the case of the hydrogenase gene and 11 strains in the case of phosphotransacetylase/acetate kinase genes. Ten strains amplified a product of the expected size with primers developed to be specific for C. thermocellum 16SrRNA primers. Two of the 13 strains did not amplify any product with the PCR primers designed for the phosphotransacetylase/acetate kinase and 16SrRNA primers. A MboI-like GATC- recognizing restriction activity was present in all of the five strains examined. The results of this study have several positive implications with respect to future development of a transformation system for cellulolytic thermophiles. Journal of Industrial Microbiology & Biotechnology (2001) 27, 275–280. Received 12 September 2000/ Accepted in revised form 20 November 2000     

Temperature-dependent Inhibition of Hypocotyl Elongation in Some Soybean Cultivars: I. Localization of Ethylene Evolution and Role of Cotyledons

Apical 2-cm hypocotyl segments from seedlings of a "short-hypocotyl"cultivar Amsoy 71, like whole seedlings, evolve about twiceas much ethylene at 25?C as at 30?C. Segments consisting oftwo cotyledons and an attached epicotyl evolve ethylene at lowrates at both 25?C and 30?C. Hypocotyl segments from seedlingsof Cutler 71 also show enhanced ethylene evolution at 25?C.Hypocotyl segments from Corsoy, a "long hypocotyl" cultivar,however, evolve ethylene at low rates at both 25?C and 30?C.Wounding of Amsoy 71 hypocotyl segments does not increase theirethylene evolution. Ethylene evolution at 25?C is reduced andthe short-hypocotyl phenomenon is reversed by partial (50%)removal of Amsoy 71 cotyledons at planting time. ¹ Journal Paper No. J-10412 of the Iowa Agriculture and HomeEconomics Experiment Station, Ames, Iowa, U.S.A. Project 2191. (Received October 5, 1981; Accepted January 28, 1982)     

A requirement for trypsin-sensitive cell-surface components for cell-cell interactions of embryonic neural retina cells

A quantitative assay was used to measure the rate of collection of a population of embryonic neural retina cells to the surface of cell aggregates. The rate of collection of freshly trysinized cells was limited in the initial stages by the rate of replacement of trypsin-sensitive cell- surface components. When cells were preincubated, or "recovered," and then added to cell aggregates, collection occurred at a linear rate and was independent of protein and glycoprotein synthesis. The adhesion of recovered cells was temperature and energy dependent, and was reversibly inhibited by cytochalasin B. Colchicine had little effect on collection of recovered cells. Antiserum directed against recovered cell membranes was shown to bind to recovered cells by indirect immunofluorescence. The antiserum also was shown to inhibit collection of recovered cells to aggregates, suggesting that at least some of the antigens identified might be involved in the adhesion process. The inhibitory effect of the antiserum was dose dependent . Freshly trypsinized cells absorbed neither the immunofluorescence activity nor the adhesion-inhibiting activity. Recovered cells absorbed away both activities. In specificity studies, dorsal neural retina cells adhered to aggregates of ventral optic tectum in preference to aggregates of dorsal optic tectum. The adhesive specificity of the dorsal retina cells was less sensitive to trypsin than the adhesive specificity of ventral retina cells which adhered preferentially to dorsal tectal aggregates only after a period of recovery.     

Preface

"Although few people die of pain,many people die in pain and even more live in pain"——IASP On October11,2004,International Association for the Study of Pain(IASP)     

混合线性模型下猪群间遗传联系的度量

采用关联指数（IC）和决定系数（CD）两种方法,度量混合线性模型遗传评估下猪群体间的遗传关联性。结果表明,加拿大安大略省的大约克夏猪、长白猪、杜洛克猪和汉普夏猪4个主要品种群体间具有良好的遗传联系。CD法既组合了数据结构和信息量,又考虑了预测误差方差和遗传变异性,是一个选择判断遗传评估精度的好方法。     

Palatability and efficacy to possums and rats of pest control baits containing bird repellents

Repellents used to reduce by-kill of birds during pest control must not compromise acceptance by target species. Two repellents combined, anthraquinone (AQ; 0.4 g kg^?1) and d-pulegone (DP; 1.0) did not reduce the palatability of blue-coloured carrot baits to laboratory rats (Rattus norvegicus); nor did DP (2.0). Green-coloured carrot baits coated with AQ, DP or AQ + DP were taken from bait stations by wild possums (Trichosurus vulpecula) and rats. Toxic (1080) bait coated with AQ (0.4) and peanut oil (0.1) had reduced palatability but was accepted by laboratory rats. However, laboratory rats did not consume enough baits coated with AQ and bacon, peanut butter, cinnamon or DP to be killed. Anthraquinone (0.4 or 0.8) plus cinnamon and DP (0.5) did not affect palatability or lethality to captive ship rats (R. rattus) or possums. Anthraquinone and DP as surface coatings on baits are therefore acceptable to possums and possibly rats, at concentrations that deter some bird species.     

PRIMARY PHLOEM REGENERATION WITHOUT CONCOMITANT XYLEM REGENERATION: ITS HORMONE CONTROL IN COLEUS

Phloem regeneration in the absence of xylem regeneration was evoked in number 5 internodes of Coleus blumei Benth. by severing xylemless phloem bundles. Its quantitative extent was estimated. To determine whether phloem regeneration is directly affected by auxin, or whether it is a secondary consequence of the auxin-dependent xylem regeneration which usually accompanies it, phloem regeneration was measured in decapitated plants from which auxin-producing leaves and buds had been removed (i.e., in “plant stumps”). In these stumps, 1% IAA in lanolin completely restored phloem regeneration to the intact plant level. In such stumps from which roots had been excised, and in excised internodes, IAA failed to restore it to this level. However, zeatin or zeatin riboside in aqueous solution applied to the bases of excised internodes receiving IAA at their apical ends restored phloem regeneration to the level of that in whole plants. When similarly tested, other cytokinins (kinetin, kinetin riboside, 2iP, and 2iPA), gibberellic acid (GA₃), glutamine, proline, sucrose, and a mixture of mineral salts failed to promote phloem regeneration. Glutamic acid, tested only once, was slightly promotive of it.