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HemAT from Bacillus subtilis (HemAT-Bs) is a commonly used heme-based [O.sub.2] sensor protein which consists of various specific hydrogen-bonding networks and is often used as a signal transducer responsible for aerotaxis. The various experiments and techniques used show that the formation of hydrogen bonds induces a conformational change in the E-helix, which is extremely essential for oxygen sensing and signal transduction in the protein.

FTIR spectroscopy is used on CO- and NO-bound sensor domain oxygen-sensing signal transducer protein HemAT and sensor domain distal mutants Y70F, T95A, R91A, and L92A to gain insight into the structure of the iron-bound ligand at ambient temperature. The comparison of the [O.sub.2], NO and CO data demonstrates that Thr95 and Tyr70 are crucial for ligand recognition and discrimination, and thus, for specific sensing of gases.

Structural and functional roles of the hydrogen-bonding network that surrounds the heme-thiolate coordination of P450(cam) from Pseudomonas putida were studied. The function of the proximal hydrogen-bonding network in P450(sub cam) is to stabilize the heme-thiolate coordination, and to regulate the redox potential of the heme iron.

Research has been conducted on the electron transfer from putidaredoxin to cytochrome P450 (sub)cam mutants. The characterization of this electron transfer has been carried out and the kinetic analysis results of this electron transfer reaction demonstrate that the dissociation constants have been pertubed for the Lys and Leu mutants and increased for Glu mutants.

Heme environment by resonance Raman spectra of both substrate-free and substrate-bound forms of the purified enzyme were experimentally investigated. It is proposed that the substrates can regulate the formation of alternative reaction intermediates by modulating the structure on both the heme distal and proximal sites in P450 aromatase.

Chemotaxis signal transducer protein DcrA from a sulfate-reducing bacterium Desulfovibrio vulgaris Hildenborough was previously shown to contain a c-type heme in its periplasmic domain for sensing redox and/or oxygen, which is the first example of a heme-based sensor protein containing a c-type heme as a prosthetic group. Heme c in DcrA would primarily work as a sensor of redox and/or oxygen for chemotaxis.

HemAT-Bs is a heme based signal transducer protein responsible for aerotaxis of Bacillus subtilis, which detects oxygen and transmits the signal to regulatory proteins that control the direction of flagella rotation. It is shown that bound oxygen is specifically sensed by the distal environment of HemAT-Bs, which has long-distance structural linkage with the signaling domain.

Cytochrome bo-type ubiquinol oxidase from Escherichia coli is a member of the heme copper terminal oxidase superfamily and catalyzes the reduction of dioxygen to water with ubiquinol-8 (Q8H2)(super 1) in the cytoplasmic membrane. The mechanism of the coupling of the oxygen activation and electron transfer with proton pumping is extensively investigated.

Gender, particularly the figure of theshōjo, plays a crucial role in the creation of heroes and the development of plots in Japanese popular texts. This paper focuses onThe Cat Returns(Neko no ongaeshi) (2002, dir. Morita Hiroyuki), one of the lesser-known films produced by Studio Ghibli. A socio-political reading and gender-sensitive analysis reveals that this film offers a deep and critical commentary on the gender order in contemporary Japan. Moreover, with its teenage girl protagonist Haru, it presents an exceptional case of ashōjo-centred anime that does not fit conventional genre characteristics. Through Haru’s refusal to become a wife in the Cat Kingdom the film criticises the expectation for young women to prioritise the pursuit of romantic relationships (ren’ai), and rejects the ideal of the Japanese housewife (shufu) as an existence of dependence in a semi-feudal social gender order. This paper views Haru’s coming-of-age story through major gender theories, and interprets the plot as a critique of what Ueno Chizuko and Nobuta Sayoko (2004) called the ‘Marriage Empire’ in Japan. We argue that the anime reflects shifting ideas on gender and at the same time presents an exceptional treatment of the need for young women to confront the social changes and gender role expectations of contemporary Japanese society. [ABSTRACT FROM PUBLISHER]