Presencia y latencia del diablo en tres comedias de Agustín Moreto
In this paper, we analyze the dramatic configuration of the devil in three plays by Agustin Moreto, Los siete durmientes (1651) El mas ilustre frances, San Bernardo (1657) y El azote de su patria (1669). The main prospect is not only the study of the stage power of a character with such a wide range of theatrical and artistic possibilities, but also his structural role in the conflict and his decisive influence on the action even when he is not actually present.
- Research Article
2
- 10.1093/aesthj/ayn004
- Apr 1, 2008
- The British Journal of Aesthetics
This paper addresses the cognitive status of making pictures, rather than their informational function. Discussion centres on the structure of pictorial space. Space of this kind is constituted from the relation between pictorial content's modal plasticity (that is, its capacity to represent actualities, possibilities, and nomological and metaphysical impossibilities) and the formative role of planar structure and idioms of recessional organization. On the basis of this, it is argued that alternative creative realizations and aesthetic significance are inherent to the structure of pictorial space itself qua pictorial. Such space is conceptually connected to the possibility of visual art.
- Research Article
- 10.14746/pt.2019.31.15
- Dec 6, 2019
- Przestrzenie Teorii
The aim of the article is to analyse the aesthetic aspects of the reception and creation of art by people with hearing impairments. For most people, hearing loss is unimaginable and is often understood only in the context of communication problems. Meanwhile, deaf people perceive their otherness completely differently. Deafness is a total experience, affecting not only the physical aspect, but also changing the perception of reality as a whole. Divergences in the way of perceiving the world, resulting from the exclusion of one of the basic senses, are particularly visible in the field of art, especially in those areas that use sound effects. The large variety of types of deafness does not allow for broad generalizations or building some kind of universal theory of reception. Therefore, from the perspective of deaf people, contact with art is very individual and intimate, which also affects the issue of their artistic creation. The author of the article touches upon the problem of the visuality of sign language and its artistic possibilities. She analyses the perception preferences of people with hearing impairments, exposing the issue of polysensory perception, and presents the most interesting artistic projects created both by the deaf and those that allow to build multidirectional relations between the parallel worlds of the deaf and hearing people.
- Supplementary Content
- 10.6092/unibo/amsdottorato/8453
- Apr 20, 2016
- AMS Dottorato Institutional Doctoral Theses Repository (University of Bologna)
This study analyses the specificities and the aesthetic-stylistic function of similes introduced by the connecting word like in Marcel Proust’s work. Proust scholars have never methodically examined simile, even though it occurs very often (more than two thousand times) throughout the Recherche. On the one hand, this absence can be explained with the little attention paid to simile, considered less important than metaphor in the collective rhetorical, linguistic and literary discourse. On the other hand, Proust considers metaphor the base of artwork and of style, and he does not bring up other figures in his aesthetic theory, even if these contribute to create his writing. Some critics remarked that the meaning of metaphore in Proust’s aesthetic idiolect includes other analogy figures, but this would not explain neither the extent of Proust’s preference, nor how it could be assimilated in a literary creation grounded on metaphor. Our study is organized as follows: first, we delve into simile’s linguistic and rhetoric features, its stylistic specificities compared to metaphor and the complex combination of the two figures in the Proustian aesthetic theory. Secondly, we comment on a selection of examples, classified in categories based on morphosyntactic criteria (nominal or frastic nature of both elements and of the link joining them to the tertium comparationis). From this analysis, a set of recurrent features that disclose the seminal use of simile in Proust can be inferred. Thirdly, we examine the function of this figure within the wider context of Proust’s work. The analysis of intradiegetic similes highlights the figure’s structural role, a tool that strengthens the network of symmetries underpinning the Recherche’s structure. Finally, the last chapter shows how similes embody in style the recognition act of the core of the self and of reality, an act that corresponds to Proust’s artistic vision.
- Research Article
- 10.29626/jas.201011.0001
- Nov 1, 2010
Carlo Zanon (1889-?) was an Italian painter and collector of guhua (ancient Chinese painting), who played an intriguing role in the art circles of Paris, Shanghai and Tokyo during the so-called floating Avant-garde movement in East Asia. Born in Schio, in the Veneto region, Zanon frequently stayed in Paris, but today he is not well known either in Italy or in France. However, his involvement in modern Chinese art was rather extraordinary. From 1928 to 1937, the art he exhibited and created in Shanghai caught the attention of the mass media in that city and elsewhere. Interestingly, Zanon's approach to modernism did not follow the examples of the avant-garde artists of Paris, but instead he painstakingly sought to develop a new painting style through collecting and studying guhua as well as Japanese ukiyo-e. Zanon's artistic approach exemplifies an alternative modernity embodied in the transformation of traditional Chinese art. Its effect on the development of Chinese painting was significant, helping to consolidate the self-confidence of guohua (national style painting) artists such as Huang Binhong (1865-1955). This paper will address the issue of modernity in East Asia by retrieving records of Zanon's exhibition and art creation in the 1920s and 30s in order to define the intriguing connection between the collecting of guhua in Europe and avant-garde movements in China.
- Research Article
- 10.5281/zenodo.1406713
- Jan 1, 2018
- Zenodo (CERN European Organization for Nuclear Research)
Театральный Плакат В.Куликова В Контексте Рекламной Коммуникации
- Supplementary Content
- 10.25643/bauhaus-universitaet.2402
- Jun 9, 2015
- Bauhaus-Universität Weimar
This doctoral thesis defines the relationship between the urban and rural in the 21st century, and focuses on food as a key component. The fact that food is, for the most part, produced in the countryside and then transported to the city has a significant influence on this very unbalanced relationship today. The main goal was to show that it is necessary to bring agriculture, urban gardening, the breeding of domestic farm animals, and beekeeping back to the city, which would have a positive affect on both the city and the countryside. All of this is already taking place at the local level, within the neighbourhoods of our cities and through the work of self-organised activities and initiatives, which have been taken up by city residents themselves. One example of this is the community garden, a new model of gardening which offers fertile ground for growing vegetables and to test various forms of co-existence, different ways of designing spaces, the creation of alternative values, and a positive vision for the future of city residents. In 2010, I co-created the community urban garden Beyond a Construction Site, which is the central part of this artistic research. Throughout the entire four-year process of creating this community garden, theory and artistic practice were intertwined, and informed one another. This community garden is an example of a self-organised and self-managed community space located in a residential neighbourhood in the centre of the city of Ljubljana, and as such is a typical example of urbanism from the bottom up. I placed the creation and development of our community garden in a dialogue with the formal way of arranging urban gardening in Ljubljana, a top-down approach, which the city has been carrying out intensively since 2007. I compared the solutions being proposed by the city of Ljubljana for organising urban gardening with the way it is organised in other European cities, the UK, and the USA. I also researched the recent rapid growth of self-organised initiatives which are focused on the local production of food and seek to find more economic and ecologically friendly models to visibly influence the future of cities and the countryside. Here, community gardens play an important role, as in addition to the production of food they are also spaces for the criticism of existing urban policies, a self-organised revitalisation of neglected spaces, and places of resilience, because they differ from that which real estate agencies, large financial companies, and city authorities desire them to be. The community garden Beyond a Construction Site has become living proof that, through a group action, the residents of a neighbourhood can influence existing city policies and the future of both their own neighbourhood and that of the entire city. The initiators of this garden are artists and architects, and we began this community garden in the context of an art festival, which also shows that art can influence the processes of everyday life and help to create much needed spaces within cities to serve various purposes. Our community garden has also shown itself to be an important platform for the exchange of knowledge on organic gardening, ecology in everyday life, and critical architecture, as well as serving to connect related initiatives. Together with these other initiatives we are stronger, and are influencing structural changes within city politics, thereby also co-creating the future of Ljubljana. This community garden is helping us to redefine our relationship with the city and re-awaken the desires and actions of residents connected with realising their fundamental right, the right to the city. My other artworks, which I am presenting in the context of this doctoral thesis, show an optimistic vision for the future of cities. The video animations Back to the City (2011) and The Right Balance (2013), as well as the accompanying collages, visualise a city of the future where urban and rural practices live together side-by-side. This vision is being realised by city residents themselves, with their active participation in the creation of community gardens, growing their own vegetables, urban beekeeping, and by having egg-laying hens in their gardens. My desire was also to present the theoretical concept and scientific research to a non-academic public, and to people without specialised training. Using the method of storytelling I included knowledge from the research into the video animations and collages. In this way my artistic work, with an intentional playfulness, challenges today’s faith in science and theoretical concepts, as well as directing attention to working with common sense, with one’s own hands, and with the earth. This can contribute to a change in the still dominant anthropocentric view of nature, which is an urgently needed change for our future. Keywords: rural, urban agriculture, community gardens, urban beekeeping, the bottom-up approach to urban planning, alternative spaces
- Supplementary Content
- 10.25904/1912/3296
- Jan 23, 2018
- Griffith Research Online (Griffith University, Queensland, Australia)
This research investigates the agency of artistic directors of subsidised major Australian theatre organisations in the post Major Performing Arts Inquiry (1999) sector. The research was conducted in response to a new generation of artistic directors commencing leadership of the major theatre companies from 2008. This new era of leadership was expected to revitalise the sector, however it remained in a perceived state of artistic and financial crisis. This thesis considers the role of the artistic director as an artistic leader of the field, and examines how the agency of this position came to be shaped by arts policy, economic and artistic forces. I argue that historical arts policies and the recommendations of MPAI altered the structures of the sector. Furthermore, while the changes these policies introduced reorganised the structure of the sector and administration of the companies, they also restricted the transformative agency of its artistic leaders to advance the artistic and economic performance of their organisations. This research uses a qualitative case study methodology. The data was collected through interviews with artistic and administrative leaders in the field, document and archival analysis and observation. The data is analysed within a theoretical framework inspired by French sociologist Pierre Bourdieu’s space of possibles, a conceptual device put forward in “The field of cultural production” (1983, p.313). Three chapters present the research. The first, a case study, examines episodes of artistic leadership at Sydney Theatre Company (STC) between 1980 and 2014. The second chapter also presents a case study that examines the career path of Aubrey Mellor and his leadership as the final artistic director of Playbox Theatre Company (Melbourne) between 1993 and 2004. The third chapter discusses the length of artistic director’s tenure as a significant constraint in the sector, with the time spent in the position revealing the effects of several artistic, economic and personal forces. The findings of the research indicate that the agency of an artistic director is predetermined through the organisation’s position in the field, established through the agendas of arts policy. Additionally, the agency of an artistic director is also profoundly influenced by the dynamic of the transition between generations of artistic leaders and the career trajectory of the individual artistic leader. These conclusions suggest the agency of artistic directors at major theatre companies is shaped through sector-wide and personal forces. Their capacity for transformative agency is limited.
- Research Article
- 10.6092/unina/fedoa/4062
- Nov 1, 2009
- Università degli Studi di Napoli Federico II
"Structure and bioactivity of bacterial glycolipids as targets for biomedical applications" - "Struttura e attività di glicoconiugati di origine batterica quali principi attivi per applicazioni in campo biomedico"
- Research Article
- 10.6280/jaaa.2009.02.06
- Jun 1, 2009
- Journal of The American Academy of Audiology
The world of nature and its countryside and wilderness environments (on land and sea) undoubtedly provide extremely important resources for artistic creation. Without nature -- without its energies, rhythms, colors, shapes, textures, sounds, harmonies, discords, and causal relations, art would never have been able to thrive. But despite the essential artistic importance of nature, in Western culture it is generally recognized that the greatest achievements of art are to be found in cities. Cities contain not only the greatest cultural resources for creating art but also the most developed facilities for presenting and preserving it. After noting some philosophically influential theories of the city, I explore the city's diverse resources for artistic creation and see how they are related to the essential structure of urban life. These resources include material culture as well as the more symbolic level of social, political, historical, and aesthetic cultural resources. In considering the question of how cities deploy their basic structure and defining resources to advance artistic creation, I give special attention to New York City's role in the artistic flourishing of the Harlem Renaissance. The paper concludes by suggesting that the city is not only a wonderfully rich source for the creation of works of art but that it also can also be considered as itself embodying a work of art, a product of creative human design and expression that can be understood, appreciated, and evaluated aesthetically.
- Supplementary Content
8
- 10.4225/03/58acfd905449f
- Feb 22, 2017
- Figshare
The thesis provides a decolonial interpretation of the cultural village phenomenon in South Africa. By cultural villages, I mean purpose-built complexes that feature staged simulations of what are supposedly the cultural aspects of indigenous communities in South Africa, mainly for the purpose of attracting tourism but also reproducing colonially rooted, stereotyped images of indigenous people. The thesis explains the meanings of this phenomenon for a subject whose locus of enunciation within the structure of the colonial power differences is that of a colonial subaltern. This interpretation is constructed around the theoretical idea of the structure-agency dialectic. This is a suitable theoretical frame for examining the cultural villages because the project of modernity/coloniality tends to constrain the potential of the social agency of the indigenous subjects of the village in developing alternative imaginations about their culture and identity. In order to effectively explain the meaning of the cultural village phenomenon from a decolonial perspective, the thesis draws on case studies of the cultural village of PheZulu Safari Park in the province of KwaZulu-Natal in South Africa, and on the quotidian experience of the traditional healer MaDlamini, in the locality of Diesploot, Gauteng province. In the former, what is represented as Zulu culture is predominantly a product of the structure of modernity/coloniality. In the latter, imaginations of Zuluness are products of indigenous agency. The two case studies provide contrasting contexts for examining the question of the tension between the influence of the structure of modernity/coloniality and indigenous agency in their respective imaginations of identity and culture in post-apartheid South Africa. The thesis demonstrates that in the cultural village of PheZulu Safari Park, the influence of the structural system of modernity/coloniality takes precedence over the agency of the indigenous people, while in the quotidian experience of the traditional healer MaDlamini in the community of Diepsloot, located outside the business of cultural village tourism, the agency of the healer plays a prominent role in determining the nature of cultural identity. The thesis reveals the cultural villages through a decolonial interpretation of the role of structure and agency in their establishment and operation. This interpretation enables the analysis to avoid the pitfall of projecting the oppressed indigenous subject as complicit in its oppression, while exonerating modernity/coloniality of its crimes against the oppressed subjects of the non-Western category. The decolonial epistemic standpoint empowers the analysis to visualize the influence of modernity/coloniality in the making of the cultural identities of the oppressed non-Western subjects without reducing these oppressed subjects into feeble and complying objects of coloniality. Thus, for instance, the cultural village experience of PheZulu Safari Park exposes the cruelty of the structural system of modernity/coloniality and yet the case of the quotidian experience of the traditional healer MaDlamini exemplifies the capability of the oppressed subject in outmanoeuvring the trapping of a colonial situation. This is an important lesson for post-apartheid South Africa, where the efforts of the subjects on the dominated side of the colonial differential require recognition against the background of a coloniality that restricts anti-system activities capable of producing a better present and future.
- Research Article
1
- 10.6092/unina/fedoa/9310
- Apr 1, 2013
- Università degli Studi di Napoli Federico II
Xenobiotics are continually introduced into the environment and it is very important to draw up an “environmental risk assessment” for these pollutants. Xenobiotics can be persistent and accumulate in the environment or undergo biotic and/or abiotic transformations leading to transformation products. The latter are known as environmental metabolites and may be more toxic and/or persistent than the parent compounds. Therefore, it is important to have information on the xenobiotic behavior in the different compartments (water, atmosphere, soil) as well as on the nature of their transformation products. The photochemical processes play an essential role in the environmental degradation of pollutants. Phototransformation studies may be used in combination with physical chemical properties and data from other studies (abiotic hydrolysis; biotransformation; adsorption/desorption) to help the assessment of the overall environmental transformations and transport of chemical pollutants. The photochemical behavior of a molecule depends on the presence of peculiar functional groups. However, given the heterogeneity and complexity of xenobiotics, it is often difficult to predict or rationalize the photochemical behavior of these molecules. In this PhD thesis the photochemical behavior of some chemical pollutants (mainly drugs and pesticides) under environmental-like conditions has been investigated. The selected xenobiotics are characterized by the presence in the molecular structure of a carbamate function or an indole moiety, two functions present in widely used bioactive compounds. In particular, direct photolysis studies have been carried out on drugs indomethacin, etodolac, loratidine and rivastigmine, on pesticides chlorpropham and phenisopham and on carbamic model compounds. Indirect photolysis of rivastigmine and nicotine have also been investigated. Moreover, for some xenobiotics photochemical experiments in soil have been performed. Direct photolysis studies have led to the determination of phototransformation kinetics, isolation and characterization of photoproducts and interpretation of the involved mechanisms. Investigation on indomethacin, a non-steroidal anti-inflammatory drug (NSAID), has evidenced the role of the aryl portion in the formation of ionic species prior to the decarboxylation, and the results give a further support to the general photodecarboxylation mechanism of arylalkanoic acids. The photochemical oxidative cleavage of C2-C3 bond through the intermediacy of peroxidic species has also been observed, and this supports the tendency of indoles to give self-sensitized photooxygenation. This type of reaction has also been observed for the other indolic drug examined, etodolac. Investigation on rivastigmine and its main human metabolite has evidenced a peculiar photochemical behavior. Both compounds undergo a β-cleavage of the benzylamine moiety resulting in photosolvolysis reaction, previously reported for benzyl ethers or esters. In particular, the photodegradation involves the tertiary amino site and leads mainly to ion-derived products characterized by departure of the Me2N-group. It is reported that amines bearing N-substituents that are capable of stabilizing the formed aminium radicals have lower oxidation potentials as compared to those with N-electron with¬drawing substituents as amides and carbamates. This could account for the unreactivity of the carbamic-N function of rivastigmine as compared with the reactivity of the benzylaminic function. Loratidine is rapidly transformed either under UV-B or by sunlight exposure. In this case the reactive site is the double bond, while the carbamate moiety is unreactive. Pesticides chlorpropham and phenisopham contain a carbamate and a bis-carbamate function, respectively; in phenisopham one of the functions is similarly substituted as in chlorpropham. Neverthless, the two pesticides behave differently: the first one undergoes a nucleophilic photosubstitution of chlorine with water on the aromatic ring, while in phenisopham photo-Fries rearrangements occur involving the cleavage of the N-aryl O-aryl carbamate moiety. However investigation on model compounds evidences that N-aryl O-aryl substitution is not a sufficient condition to have a photo-induced breaking of the carbamate bond. This breaking is completely overcome in the presence of a chlorine on the aromatic ring. Moreover, substitution on the carbamic nitrogen as well as the presence of a N-substituent in the O-aryl moiety appears determinant to accelerate the photo-Fries reaction. All photochemical experiments evidence the determinant role of water. This is probably due to the fact that water can favor photoionization reactions, stabilize ionic intermediates and trap electrophilic species. Indirect photolysis investigations have been performed on rivastigmine and nicotine in Clermont-Ferrand (France) in collaboration with Laboratoire de Photochimie Moléculaire et Macromoléculaire-University Blaise Pascal. The results show that the degradation rate of both compounds depends on the HO• source (H2O2, nitrates, nitrites). Faster degradation has been observed in the presence of nitrates and nitrites and is probably due to reactions between the xenobiotics and photogenerated reactive nitrogen species. For rivastigmine the formation of nitro derivatives has been confirmed by LC-MS. Nitro compounds are often more toxic than the parent compounds, and hence for a complete environmental risk assessment the reactivity toward hydroxyl radical and also toward nitro reactive species that are naturally present in surface waters should be considered. Less satisfying has been the investigation on the photochemistry in soils. Despite the simple synthetic model soils used each compound examined behaves differently depending on the light absorption property and on the formation of saline bonds due to the presence of acidic or basic reactive sites. In addition to these factors in real soils other factors should be considered as the presence of microorganisms or xenobiotics, the type of texture, the pH, etc. In conclusion, the whole of the results give information on the photochemical behavior of different xenobiotics under environmental-like conditions. From a chemical point of view they give a deeper insight into the substituent and solvent effects in the photochemistry of some important compound classes as indoles, benzyl derivatives and carbamates. Therefore, these studies could allow to develop theoretical models for the prediction of the environmental fate of xenobiotics.
- Research Article
1
- 10.4467/20843925sj.15.010.4232
- Feb 25, 2016
- Scripta Judaica Cracoviensia
Interwar Krakow was a vibrant cultural center in newly independent Poland. Jewish intelligentsia played a significant part in preservation of Krakowian culture, but also endowed artist and cultural institutions. In a shadow of renowned Maurycy Gottlieb, there is his great collector and promoter of his artistic oeuvre, Rudolf Beres (1884-1964). The core of the collection was inherited from his father Emil. Rudolf, who arrived to Krakow to study law, brought these pictures with him, and with time extended the collection, not only with Maurycy Gottlieb’s artworks, but also other distinguished Polish artists. As a director of the Krakow Chamber of Commerce and Industry he played an influential role in the city and country scene. As a member of Solidarnośc – Krakow B’nai Brith chapter, he was active in the cultural events and ventures in the city. He was the main force behind the famous exhibition of Maurycy Gottlieb’s of 1932 in the National Museum in Krakow. Rudolf collected extensive information on Maurycy in order to commemorate his life and promote artistic oeuvre of the first Jewish artist of such significance. His home art gallery, mostly because of Gottlieb’s collection was visited by various Jewish activists; for example Hayim Nahman Bialik. Moreover, Rudolf planned to exhibit Maurycy’s work in Tel Aviv. With a group of B’nai B’rith members he traveled with his wife to visit Palestine. He was a close friend of Feliks Kopera, the director of the National Museum in Krakow, for which he extensively organized money collection for erecting a new galleries’ building. The paper presents forgotten and unpublished facts about a Jewish art collector of Krakow, a person whose art works he once possessed and cherished, are now in various museums and private collections as a result of WWII and communist regime. I bring the man back from obscurity of history’s selectiveness. The historical documents, family heirlooms and discovered war memoirs of Rudolf construct the past of the great Jewish citizen of Krakow without whom Maurycy Gottlieb could have been unknown as much as he is known now.
- Research Article
- 10.26180/5d9ffeafc2607
- Oct 11, 2019
- Figshare
14th CIRN (Community Informatics Research Network) Prato Conference 2017, 25-27 October 2017Monash University Centre, Prato, ItalySpecial Stream: Art as Archive: Archive as Art & The Imagined ArchiveI assisted with the preparation of the conference, presented a paper and co-authored another presentation.AbstractAlong with archives and museums, libraries have the public mission to preserve the cultural heritage for their communities. Several cases are known of pre-existing buildings with a non-library function that have been recycled and renovated worldwide. In other cases a specific plan has been put in action to re-evaluate and give new shape to emblematic buildings which are a strong part of the history and culture of a specific community. One successful example of the latter is the Lazzerini Documentation and Cultural Centre of Prato, the recovery of which, started in 2000 and concluded in 2009, was aimed at designing a new larger location in the former Campolmi Textile Factory, a well-known example of the manufacturing tradition of the city. The paper investigates the case of the Lazzerini Library and the symbolic and critical role of historical building-renovated libraries, examining how they persist, not only as guardians of documentary material and memory, but as an expression of cultural heritage preservation themselves.Background to the ConferenceSince the founding colloquium in 2003, the Community Informatics Research Network (CIRN) has been marked by informality, collegiality and interdisciplinary thinking, bringing together people from many different countries in an ideal Italian setting. Themes have ranged across issues such as privilege, gender and sexual identities, forms of knowledge, documentation, participation and community-based research, power, ideals and reality, and measurement. For this edition, we chose a theme that traverses new spaces and boundaries and provokes thinking (and action) between different communities of interest. Thus, those focussed in more conventional activity in community, development and archival informatics may be provoked by what those in the art and archives space have to show and tell, and the reverse also applies.2017 special theme: Art as Archive: Archive as Art & The Imagined Archive There has long been discussion about the relationship between art and archives, not just in the sense that archives may represent curated collections relating to specific artists or forms of art, but that art may be used to provide new ways of conceiving what is in archival collections, and new ways of thinking about the nature and meaning of those collections. These themes were explored by a number of papers discussing radical archives at Prato 2016, but in 2017 we went further exploring the relationship from multiple perspectives.
- Research Article
- 10.6092/unina/fedoa/8790
- Nov 30, 2011
- Università degli Studi di Napoli Federico II
The present Ph.D. thesis has focused on tetrameric hemoglobins (Hbs), both recombinant and natural, both from human origin and Antarctic fish, using a multidisciplinary approach based on spectroscopic, crystallographic and computational techniques. In particular the main scope of the research has been the elucidation of two still unsolved problems in the chemistry of tetrameric Hbs: 1) the role of the bis-histidyl heme coordination in the Hb function and oxidation process and 2) the role of the tertiary and quaternary structure in the modulation of the Root effect (namely drop of oxygen affinity with loss of cooperativity at low physiological pH). The first topic has been mainly approached through a comparative experimental (spectroscopic and crystallographic) / computational study of the β-subunits of human hemoglobin (β-HbA) and of the recombinant β-subunits Hb from Antarctic fish Trematomus bernacchii (β-HbTb), whose heterotetramer, in the ferric state, forms a mixture of aquo-met at the α-subunits and bis-histidyl adduct at the β-subunits. Similarly to the human β-chains, β-HbTb self-assembles to form the homotetramer (β4-HbTb); however, the latter quantitatively forms reversible ferric and ferrous bis-histidyl adducts, which are only partially present in the human tetramer (β4-HbA). The molecular dynamics study of the isolated β-subunit of the two Hbs indicates that the ability to form hemichrome is an intrinsic feature of the chain; moreover, the greater propensity of β-HbTb to form the bis-histidyl adduct is probably linked to the higher flexibility of the CD loop region. These findings are in perfect agreement with the X-ray structure of β4-HbA in the ferric (solved in this thesis) that hosts only aquo-met coordination. The mechanism of hemichrome formation was also investigated by determining the x-ray crystal structure of the fully oxidized Hb from Antarctic fish Trematomus newnesi and by performing a Resonance Raman microscopy study on the Hb crystals from a sub-Antarctic fish (Eleginops maclovinus). The second topic has been investigated through a combined spectroscopic (resonance Raman (RR) /Vis microspectroscopy) and X-ray crystallographic study of oxygen (O2) and nitric oxide (NO) binding to the T-state HbTb (Root-effect Hb) crystals at two different pHs, 6.0 and 8.4. The choice of these pH values is justified by the known tertiary structural differences of their X-ray structure in deoxygenated forms at different pH values. Oxygen binding curves have shown that the low -to- high pH transition induces 2-3 fold increase in oxygen affinity and that about half of the cooperativity present in solution is retained in the crystal. The simultaneous X-ray data collection, on the T-state nitrosyl-HbTb crystals assisted by online Raman acquisition, at the synchrotron Swiss Light Source (PXII beamline), clearly indicates an X-ray induced NO-photodissociation, providing a general physical explanation of the low content of nitrosyl-hemoglobin structures deposited in the Protein Data Bank. RR microscopy supported crystallography in choosing the X-ray dose feasible to collect a fully nitrosylated hemoglobin. The comparison between fully NO ligated and photolized crystal refined structures provides an elegant evidence of heme-heme communication mediated via the CDα region, that involves those interactions that were suggested to be contributor to the Root effect in HbTb. In addition this Ph.D. thesis also focused on a study at cellular level (via Raman imaging and Optical Tweezers) of healthy and C / S anemic erythrocytes [containing HbS (β6Glu → Val) and HbC (β6Glu → Lys)]. The different photo-sensibility and rigidity of healthy, C and S erythrocytes showed that the Raman micro-spectroscopy analysis combined with the use of Optical Tweezers offers enormous potential in the diagnosis of normal and diseased cells.
- Supplementary Content
- 10.25904/1912/132
- Jul 2, 2020
- Griffith Research Online (Griffith University, Queensland, Australia)
Investigating the Role of Past Behaviour and Habits in Health Behaviour