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利用次世代基因定序技術探討我國急性腹瀉患者之腸道菌叢表現

依據世界衛生組織2013年調查研究顯示,全球每年約有29%的孩童 (超過兩百萬名) 因腹瀉及肺炎而死亡,而在我國腹瀉群聚亦佔傳染病防治之大宗,尤其2020年受新冠肺炎(COVI-19) 疫情影響,台灣民眾均留在國內旅遊,腹瀉案件急速增加,且因適逢旅遊熱門旺季加上中小學開學之際,經常出現規模上百人的腹瀉群聚,危害民眾健康。現階段急性腹瀉病人的治療多以支持性療法為主,然而目前應用糞便移植重建腸道菌叢已是包括癌症在內的重症醫療方向之一。本研究應用次世代基因定序技術偵測微生物16S rRNA 的高變異區域進行急性腹瀉患者腸道微生物菌相組成、菌種豐富度分析及菌種鑑定,希望透過偵測急性腹瀉患者的腸道微生物相分析有助於理解腹瀉患者與健康人體腸道菌叢的差異,可提供未來臨床治療參考,亦可藉此推動從家庭到社區的全民健康促進,打造健康優質的生活品質。

Bacteria with Headphones

I first found out about the Young Scientist competition last year, in 2021. I thought it was an interesting and challenging opportunity; something that could take students out of their comfort zone. I researched for some inspiration online and found a website with all the different types of project ideas. While reading about the experiments, I stumbled upon a project relating the music to bacterial growth. It sounded ridiculous at first, but I soon realized it was the right project for me. It intertwined music and biology- form of art I’ve been involved in since the age of 9, and one of my favorite subjects and a field I want to work in in the future.

利用麵包蟲腸道菌降解聚丙烯並探討其優化策略

塑膠對環境危害甚深,雖已有研究證實部分昆蟲可降解塑膠類的聚苯乙烯(PS),但關於聚丙烯(PP)的生物降解研究很少,也沒有進一步透過腸道菌相分析,鑑定出負責降解的菌種。因此我們希望利用麵包蟲生物降解PP,透過16S rRNA定序分析找出可降解PP的潛力菌種,解決塑膠垃圾對環境造成的傷害。我們的實驗結果顯示,麵包蟲能攝食PP並生長,且加入濕料及利用糞便移植腸道菌相能增加麵包蟲對PP的消耗量,證明麵包蟲能攝食PP與腸道菌相有關。利用次世代基因定序分析腸道菌相,麵包蟲攝食PP後腸道菌相有極為顯著的變化,其中腸道菌Pseudomonas stutzeri顯著增多,經實驗證實此菌可降解PP,且在37oC、中性環境的降解效果較佳,一星期約降解3.4 %的PP。我們所使用的方法可快速篩選出能降解PP的菌種。

探討番茄根圈菌對農桿菌的生物防治

前人以含農桿菌 C58(Agrobacterium tumefaciens C58)土壤接種番茄小苗後,發現有些番茄未產生腫瘤,故推測其土壤根圈中,有能抑制農桿菌 C58的細菌。本研究從番茄小苗根圈分離並純化培養細菌,再透過抑制圈實驗測試分離菌。結果發現分離株YA7-1,有顯著抑制農桿菌 C58的效果,進而測試其他農桿菌菌株。結果顯示YA7-1對多種農桿菌具拮抗能力,且不同於現行的生物防治菌農桿菌(Agrobacterium radiobacter K84 and K1026)有高選擇性限制。定序其16S核糖體核糖核酸基因片段,序列比對為節桿菌屬(Arthrobacter)。經由接種試驗得知YA7-1對番茄沒有致病力,且預先接種於根部時,可降低土壤中農桿菌誘導腫瘤的機率。測試YA7-1對其他植物病菌及非病原微生物的抑制效果,發現YA7-1具有廣效性的抑菌能力。藉由分析培養液上清夜的實驗可得知YA7-1的抑菌因子為分泌物質。完成YA7-1全基因體定序後,找到四種可能被YA7-1分泌且具有抑制性的次級代謝物。未來將繼續找尋YA7-1的抑菌物質與機制,來完善對根癌農桿菌或其他植物病原菌的生物防治。

探究Nocardiopsis菌落環狀紋路與相鄰同宗菌落間隙的成因

我們研究自黑液污染土壤篩選出的Nocardiopsis(擬諾卡氏菌)菌落環狀紋路的成因,發現環狀紋路形成具有遺傳性且可能是基因變異產生。在低營養濃度(Tryptone濃度小於1g/L)條件下,菌落紋路明顯,推測是由於基層菌絲無法取得足夠養分供給氣生菌絲,氣生菌絲無法生長,直到基層菌絲往外拓展至有足夠的營養物質的區域,氣生菌絲才再次開始生長,因而產生一環一環的不連續生長帶。 此外我們發現多個Nocardiopsis菌落之間,會因抑制物質作用產生間隙,此間隙大小受營養物質濃度、菌落間初始距離、周圍菌落數目的影響,且其機制與形成環狀紋路的機制並不相同,可能與菌落間偵測感應等複雜機制有關。我們萃取此抑菌物質送液相層析串聯質譜儀(LC-MS/MS) 鑑定其成分,發現抑制物質可能是Streptogrisin C或其他非蛋白質物質。深入研究Streptogrisin C的濃度與抑制Nocardiopsis生長的關係,以及其他抑制物質的可能性是我們未來的研究方向。

探討I類與II類的HDAC基因調節細胞週期之互補功能

組蛋白脫乙醯基酶 (HDAC) 會調節染色體結構,提升基因表現。除了調控基因表現以外,HDAC基因家族中的 I 類已知有調節細胞週期的功能,但 II 類調節細胞週期之研究甚少。而癌症臨床用藥HDAC抑制劑會同時阻斷 I 和 II 類之功能而產生副作用。因此本研究以釀酒酵母為對象,分析 I 類的RPD3、 II 類的HDA1基因對細胞週期之影響,以及HDAC基因剔除菌株在面臨DNA複製壓力時的變化。結果顯示同時失去 RPD3 、HDA1 基因的菌株 S 期檢查點功能損壞、細胞滯留於 G2/M 期,且在DNA複製壓力環境下死亡。爲釐清此菌株死亡的原因,實驗剔除在S期和G2/M期皆具調節功能的 MAD2 基因。得知 HDAC 基因和 MAD2 在S期的DNA複製起步期分別調控不同路徑;在DNA複製衝刺期則調控同一路徑。也發現RPD3 基因在維持細胞S期檢查點正常作用扮演較重之角色,而 HDA1 則扮輔助的功能。

Using Focused Ultrasound and Pulsed Ultrasound as a Solution to Viral Infection

Viruses Both enveloped and non-enveloped viruses conceal their membrane-penetrating peptide, usually within a glycoprotein of the virion membrane, inside the coat, or within the virion lumen. Cellular signals expose membrane-penetrating peptides that influence the virus during its entry. Instances of cellular signals regulating virus entry include receptors, enzymes, and substances like proteases, metal ions, and reducing agents. Recently, motor proteins or virus maturation have been seen to regulate virus entry through mechanical processes.

探討清冠一號對小鼠腸道菌相的影響

部分COVID-19的確診者及未感染的民眾有服用清冠一號的需求與經驗,並且大部分民眾出現腹瀉的狀況。因此,我們想了解服用清冠一號是否會對腸道菌相造成影響,以及停用後腸道菌相是否會恢復為未服用前的樣子。本研究設計連續管餵小鼠清冠一號5天,在這5天期間及停止管餵5天後測量小鼠的體重與採集糞便檢體。以此實驗來探討服用清冠一號前、中、後,小鼠的腸道菌相變化。我們發現,服用清冠一號期間小鼠的腸道菌豐富度及多樣性降低,而停止管餵5天後,整體的腸道菌組成趨向服用清冠一號前,並且豐富度及多樣性也有恢復;在體重方面,管餵清冠一號第1天後,體重下降最為明顯,停止管餵後,體重逐漸上升。

醃漬物中的乳酸菌對胃細胞的影響分析與探討作為食用益生菌之可能

研究發現食用醃漬食品能夠讓腸道菌相平衡、提高免疫力、降低血脂血壓等。科學家們從這些食物中分離出乳桿菌(Lactobacillus)、鏈球菌(Streptococcus)和明串球菌(Leuconostoc)等。本研究希望從醃漬食品中分離出能夠維持腸道健康的益生菌。首先,我們從台北的傳統市場收集醃漬食品,利用選擇培養基分離細菌。通過PCR確認為乳桿菌屬後,測量他們的胞外多醣產量。我們發現菌株1-1、 3-2、 3-4、 3-6-2、和 3-8能夠在含有低酸和膽鹽的環境生存,並測試他們對人類胃細胞的毒性。在MOI=10的情況下,所有菌株都能維持細胞80%的生存率。但是,菌株1-1、 3-2、 3-4、 3-6-2、和 3-8的細胞貼附能力非常弱。除此之外,我們發現菌株PV15、 1-1、 3-2、 3-4、 3-6-1、 3-6-2、和 3-8的上清液能小幅度地抑制大腸桿菌生長能力。未來,我們希望能進行腸道細胞的實驗(CACO-2),並利用動物來檢測菌株維持腸道健康的能力。

Revolutionizing Metabolic Health: The Therapeutic Potential of Next-Generation Probiotic Akkermansia Strains (Z62, IR119) for Metabolic Syndromes

The human gut microbiome is integral to digestion, overall health, and metabolic disorder imbalances. Recent advancements in fecal microbiota transplantation (FMT) have highlighted the therapeutic promise of restoring healthy gut microbiota in populations with high incidences of diseases. Focusing on fecal DNA samples from healthy Asian individuals, this study examines the potential of novel Akkermansia strains, specifically Akkermansia muciniphila (Z62) and Akkermansia massiliensis (IR119), as next-generation probiotics for mitigating metabolic syndrome. A key aspect of the study is the investigation of short-chain fatty acids (SCFAs), which are produced and play a crucial role in regulating metabolic processes. SCFAs such as butyrate, acetate, and propionate are essential for energy provision to colon cells and exerting anti-inflammatory effects. The methodology involves selecting two Akkermansia strains, analyzing them through 16S rRNA and WGS, evaluating their growth and survival rates under acidic and bile-salt conditions, alongside their cell adhesion capabilities. The study focuses on the production of key short-chain fatty acids (SCFAs) and tryptophan derivatives by bacteria in regulating metabolic processes, as well as their anti-inflammatory effects on colon cells. Through in vitro assays, both strains exhibited survival in acidic/bile-rich conditions, though Z62 demonstrated superior adhesion to Caco-2 cells, suggesting a higher colonization potential. Metabolomic analysis revealed both strains produce SCFAs, including propionic and acetic acids, and indole metabolites, such as indole-3-propionic acid and indole-3-acetic acid, which are known to influence lipid metabolism and insulin sensitivity. In adipocyte cell models, IR119 significantly reduced lipid accumulation, while Z62 increased lipid presence. Furthermore, IR119 reduced pro-inflammatory cytokine levels, including IL-6 and TNF-α, suggesting potential for inflammation mitigation. The future potential of IR119 as a therapeutic probiotic is extraordinary in addressing complex metabolic and inflammatory diseases, which open new avenues for managing chronic inflammatory conditions like type 2 diabetes and cardiovascular disease. Future clinical trials could refine IR119’s efficacy, positioning it as a leading probiotic in preventive and therapeutic contexts.