A 3D Model of the Membrane Protein Complex Formed by the White Spot Syndrome Virus Structural Proteins

Outbreaks of white spot disease have had a large negative economic impact on cultured shrimp worldwide. However, the pathogenesis of the causative virus, WSSV (whit spot syndrome virus), is not yet well understood. WSSV is a large enveloped virus. The WSSV virion has three structural layers surrounding its core DNA: an outer envelope, a tegument and a nucleocapsid. In this study, we investigated the protein-protein interactions of the major WSSV structural proteins, including several envelope and tegument proteins that are known to be involved in the infection process.In the present report, we used coimmunoprecipitation and yeast two-hybrid assays to elucidate and/or confirm all the interactions that occur among the WSSV structural (envelope and tegument) proteins VP51A, VP19, VP24, VP26 and VP28. We found that VP51A interacted directly not only with VP26 but also with VP19 and VP24. VP51A, VP19 and VP24 were also shown to have an affinity for self-interaction. Chemical cross-linking assays showed that these three self-interacting proteins could occur as dimers.From our present results in conjunction with other previously established interactions we construct a 3D model in which VP24 acts as a core protein that directly associates with VP26, VP28, VP38A, VP51A and WSV010 to form a membrane-associated protein complex. VP19 and VP37 are attached to this complex via association with VP51A and VP28, respectively. Through the VP26-VP51C interaction this envelope complex is anchored to the nucleocapsid, which is made of layers of rings formed by VP664. A 3D model of the nucleocapsid and the surrounding outer membrane is presented

Usage of anion exchange chromatography to purify major proteins in the pericarp of jelly fig (Ficus awkeotsang Makino) achenes

愛玉 (Ficus awkeotsang Makino) 多生長在台灣山區。在愛玉子胞外蛋白質中，以三種蛋白質含量最為豐富，分別為果膠甲酯酶 (pectin methylesterase, PME)，幾丁質酶 (chitinase) 和似索馬甜蛋白質 (thaumatin-like protein；TLP)。隨著科技的發展，可輕易利用酵母菌、大腸桿菌等微生物系統，以低成本的條件大量生產表現重組蛋白質。但於愛玉子胞外大量表現的蛋白質中，多為已知功能的酵素，在微生物蛋白質表現系統中卻易使酵素失去活性。過去的研究中也顯示，使用大腸桿菌系統生產愛玉果膠甲基酯酶 (PME) 確實會使此蛋白質失去寶貴的活性功能。根據細菌學研究已知，一般生物體內的抗生素不但可以單獨作用，也可透過與不同種類的抗生素同時作用，此協同作用使生物能更適切的對抗環境壓力。因此本研究透過建立一純化流程，可快速取得高純度的原態(native form) 愛玉子胞外酵素蛋白質。本研究根據早期研究，愛玉子胞外大量表現的蛋白質皆耐酸、耐熱，因此選擇兩種陰離子交換層析管柱，DEAE和HiTra Q (Q) 管柱進行愛玉子胞外蛋白質的分離及純化。實驗結果顯示強電性的HiTrp Q管柱較弱電性的DEAE管柱在分離愛玉子胞外蛋白質有較好的成效。選擇Q管柱進行後，測試分離及純化的最適化條件。本研究中證實，利用Q管柱對愛玉子胞外蛋白質的純化及分離效果佳，且原態蛋白質的純度也高。但研究中也顯示，除大量表現的三個愛玉子胞外蛋白質，尚有約40% - 50% 的低表現量蛋白質存在。此結果在計算蛋白質含量百分比和銀染分析實驗中獲得證實。含量很高的低表現量蛋白質推測與已知的高表現量蛋白質相關，可能是具有協同作用的蛋白質。未來可依此結果，增加愛玉子胞外蛋白質萃取量和加入不同功能的管柱進行純化，分析低量蛋白質是否為新抗生素的可能性。中文摘要.......................................................................................................................................... i 英文摘要......................................................................................................................................... ii 目錄................................................................................................................................................ iii 表目錄............................................................................................................................................ iv 圖目錄............................................................................................................................................. v 第一章 前言................................................................................................................................. 1 第二章 材料與方法..................................................................................................................... 2 一、植物材料來源 ..................................................................................................................... 2 二、愛玉瘦果胞外蛋白質萃取 ................................................................................................. 2 三、純化胞外蛋白中的主要蛋白質 ......................................................................................... 2 四、聚丙烯酰胺膠體電泳 (sodium dodecyl sulfate polyacrylamde gel electrophoresis；SDS-PAGE) 分析純化後蛋白質 ........................................................................................................ 2 五、銀染分析純化後蛋白質 ..................................................................................................... 3 六、BCA蛋白質定量法 ............................................................................................................ 3 第三章 結果................................................................................................................................. 4 一、比較兩種陰離子交換層析管柱純化愛玉子胞外蛋白質的效益 ..................................... 4 二、愛玉子胞外蛋白質於Q管柱分離純化最適化 ................................................................ 4 三、純化及分離愛玉子胞外的主要蛋白質 ............................................................................. 5 四、純化及分離愛玉胞外的次要蛋白質 ................................................................................. 5 第四章 討論................................................................................................................................. 6 第五章 結論................................................................................................................................. 7 第六章 參考文獻.........................................................................................................................

Exploring the Impact of Service Recovery Attitude on Customer Satisfaction and Loyalty in the catering service ─ comparing high versus low service level

[[abstract]]餐飲業的發展已漸漸成為台灣商業服務業中主要的趨勢，外出享受美食的習慣已然融入台灣生活之中，但卻因為每間餐廳服務性質的不一，再加上無法避免的人為疏失，導致餐飲業經常發生服務疏失。在面對服務疏失的情況下，本研究探討顧客對於餐飲業者的補救態度及補救後的滿意度與忠誠度之間的關係及影響，且以兩個不同的餐廳類別包括高服務水準的餐廳及低服務水準的速食餐廳，來做為比較顧客對餐廳業者的補救態度、滿意度及忠誠度是否有顯著差異。本研究採用便利抽樣方式，共取得250份有效樣本，以迴歸分析驗證研究假設。研究結果如下：1.補救態度對顧客滿意度有正向影響。2.顧客滿意度對顧客忠誠度有正向影響。3.顧客滿意度完全中介補救態度對顧客忠誠度的影響。4.在高、低服務水準的比較下，顧客對補救態度有顯著差異。5.在高、低服務水準的比較下，顧客對顧客滿意度沒有顯著差異。6.在高、低服務水準的比較下，顧客對顧客忠誠度沒有顯著差異。本研究依據上述研究結果，提出具體的管理意涵及建議協助餐飲業者審定出有效的補救策略。[[abstract]]ThedevelopmentofcateringservicehasgraduallybecomethemaintrendinTaiwan’sbusinessservicesector,andthehobbyofeatingoutisalreadyintegratedintoTaiwan’slifestyle.However,theserviceofeachrestaurantisdifferent,andhumannegligencetoleadingservicefailureisunavoidable.Thisstudyexplorestherelationshipbetweencustomer’sservicerecoveryattitude,servicerecoverysatisfactionandloyalty.Besides,twodifferenttypesofrestaurantsarecompared,includingahighservicelevelrestaurantandafastfoodrestaurant.Adoptingconveniencesampling,250effectivequestionnaireswerecollected.Weuseregressionanalysistoprovethehypotheses.Theresearchoutcomeshowsthat：1.Recoveryattitudehasapositiveeffectoncustomersatisfaction.2.customersatisfactionhasapositiveeffectoncustomerloyalty.3.TherelationshipbetweenRecoveryattitudeandcustomerloyaltyiscompletelymediatedbycustomersatisfaction.4.There’sasignificantdifferenceincustomer’srecoveryattitudeamonghigh/lowservicelevelrestaurantguests.5.There’snosignificantdifferenceincustomersatisfactionamonghigh/lowservicelevelrestaurantguests.6.There’snosignificantdifferenceincustomerloyaltyamonghigh/lowservicelevelrestaurantguests.Accordingtotheresultsabove,specificmanagementimplicationandsuggestionstothecateringserviceareproposedonhowtherestaurantscansetuptheeffectiverecoverystrategy