The initial steps involved in the assembly of normally soluble proteins into amyloid fibrils remain unclear, yet over 20 human diseases are associated with proteins that aggregate in this manner. Protein surface modification is a potential means of mapping the interaction sites in early oligomers that precede amyloid formation. This dissertation focuses on the use of covalent labeling combined with mass spectrometry to elucidate the structural features of Cu(II)-induced β-2-microglobulin (β2m) amyloid formation. An improved covalent modification and MS-based approach for protein surface mapping has been developed to address the need for a reliable approach that ensures protein structural integrity during labeling experiments and provides readily detectable modifications. This approach involves measuring the kinetics of the modification reactions and allows any local perturbations caused by the covalent label to be readily identified and avoided. This MS-based method has been used to study human β2m, a monomeric protein that has been shown to aggregate into amyloid fibrils in dialysis patients leading to dialysis-related amyloidosis. Under conditions that lead to β2m amyloid formation, reactions of β2m with three complementary covalent labels have been used to identify the Cu(II) binding site, metal-induced conformational changes, and the oligomeric interfaces. Results confirm that Cu(II) binds to His31 and the N-terminal amine. Binding to these residues causes several structural changes in the N-terminal region and ABED β-sheet which likely enables formation of oligomeric intermediates. The covalent labeling data indicate that the pre-amyloid β2m dimer has an interface that involves the antiparallel arrangement of ABED sheets from two monomers. Moreover, our covalent labeling data allowed us to develop a model for the tetramer in which the interface is mediated by interactions between D strands of one dimer unit and the G strands of another dimer unit. Lastly, the selective covalent modification approach has been used to delineate the structural changes in β2m after interaction with Cu(II), Ni(II), and Zn(II) and their effect on its aggregation. Our covalent labeling data indicates that the unique effect of Cu(II) appears to be caused by the site at which the metal binds the protein and the conformational changes it induces.

Polyketides are a class of natural products that exhibit remarkable structural and functionally diversity and are highly sought after due to their medicinally important activities. For many decades now, polyketide synthases (PKSs), the mega-enzymes responsible for biosynthesis of polyketides have been the focus of extensive investigation to make new polyketides by polyketide engineering strategies. While there are many established methods to investigate polyketide enzymes and biosynthesis mechanisms, they have substantial shortcomings that have limited the extent of success with polyketide engineering efforts. This thesis focuses on developing simple, flexible yet powerful tools for examining polyketide biosynthesis by overcoming some deficiencies in currently used techniques. Reactive heterocylces have been designed for direct labeling of key polyketide synthase enzymes to provide a direct insight into its functions and mechanisms. First β-lactones and then β-lactams have been used as small molecule probes to perform site-specific labeling of acyl carrier proteins and further used for mechanistic interrogation of key steps in polyketide biosynthesis. The utility of these probes has been demonstrated by comparison to traditional probes and has been successfully applied to examine substrate selectivity of keto synthases, key enzymes in polyketide biosynthesis. The applications of the tools described in this manuscript only scratch the surface of their capabilities and are expected to significantly aid in the study of new and existing PKS systems leading to improved understanding of how these extraordinary biosynthetic machines function.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23923号 / 工博第5010号 / 新制||工||1782(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 浜地 格, 教授 森 泰生, 教授 秋吉 一成 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

There has been a widely held perception for a long time that the automotive industry largely consists of male-dominated professions. It is likely that this association will persist in the future, as there are deeply rooted structures and norms that uphold gender labeling within the automotive industry. The purpose of our study is to investigate women's perceptions of leadership and its impact on gender equality in the Swedish automotive industry. Previous research has primarily focused on the leadership perspective and undermined the experiences of female industrial workers. By focusing on women's perceptions and experiences of their immediate supervisors and their leadership, this study contributes to a deeper understanding of the barriers and challenges that women face within the automotive industry. The concepts of transformative and transactional leadership were used to differentiate different leadership behaviors. A qualitative method, based on semi-structured interviews, was employed to conduct the investigation. The results revealed that leadership has a significant impact on the social work environment, and that transformative leadership can positively influence the male-dominated automotive industry from a female perspective. / Det har länge funnits en vedertagen uppfattning om att fordonsindustrin till stor del innebär mansdominerade yrken. Det är sannolikt att denna association kommer att bestå i framtiden, då det finns djupt rotade strukturer och normer som upprätthåller genusmärkningar i fordonsindustrin. Syftet med vår studie är att undersöka kvinnors uppfattning av ledarskap och dess inverkan på jämställdhet i svensk fordonsindustri. Tidigare forskning har i huvudsak fokuserat på ledarskapsperspektivet och underminerat de kvinnliga industriarbetarnas erfarenheter. Genom att fokusera på kvinnors uppfattningar och erfarenheter av närmste arbetsledare och deras ledarskap, bidrar denna studie till en djupare förståelse av de hinder och utmaningar som kvinnor möter inom fordonsindustrin. Begreppen transformativt respektive transaktionellt ledarskap användes för att särskilja olika ledarskapsbeteenden. För att genomföra undersökningen användes en kvalitativ metod, baserad på semistrukturerade intervjuer. Det framgick av resultatet att ledarskapet har en stor inverkan på den sociala arbetsmiljön och att ett transformativt ledarskap kan påverka den mansdominerade fordonsindustrin positivt ur ett kvinnligt perspektiv

Society’s views about mental illness can influence their views regarding police-response strategies used with the mentally ill. The purpose of this study is to analyze the question: does mental illness impact perceptions of delinquent behavior and police responses? It is important to understand the effects of these interactions to better assist those affected by mental illness and avoid uncertain risks/injuries to the police and citizens involved in an incident. Labeling theory suggests that people may come to identify and act in ways that reflect how others label them as well as come to define mentally ill individuals in accordance with the label. My interest in understanding how police label mentally ill individuals as either deviant (out-of-the-norm) or criminal because of their condition motivated me to explore what other people thought about this. This study used survey analysis to collect data from 349 Facebook participants. Participants were randomly assigned to 1 of 2 scenarios (excerpt A and excerpt B). The only difference between these two scenarios is that excerpt B directly relates to mental illness while excerpt A does not mention mental illness. In relation to labeling theory, I predict mental illness will impact the perception people have about how police may respond to situations involving the mentally ill. Further studies should expand this research to examine this connection more thoroughly. The broader implications of this research is that it could create awareness as to ways in which to improve police training tactics that could in turn result in better support between mental health services and law enforcement.

Research has indicated that individuals with ASD have deficits in the ability to correctly identify and interpret the emotions and feelings of others. The ability to recognize the emotions of others has shown to be extremely beneficial in a number of ways. On the other hand, the inability to recognize the emotions of others has been linked to a number of negative outcomes, including inappropriate behaviors, as well as mental health, personal, social, and academic difficulties. The purpose of the current study was to extend the previous literature on effective strategies for teaching individuals with ASD to correctly label the situation-based emotions of others. Overall, the current study’s results suggest that an intervention package combining animated videos with prompt delay, error correction, and reinforcement procedures was effective in teaching participants the ability to label situation-specific emotions. Additionally, the current study’s results also supported the idea that individuals with ASD have stronger deficits in recognizing negative emotions, such as sad, mad, and afraid, as compared to positive emotions, such as happy. Future research should continue to focus on exploring the generalization and maintenance of these results.

No description available.

No description available.

No description available.

No description available.