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Serratia marcescens S-95, which displayed an unusually high degree of resistance to aminoglycosides, including kanamycins and gentamicins, was isolated in 2002 from a patient in Japan. The resistance was mediated by a large plasmid which was nonconjugative but transferable to an Escherichia coli recipient by transformation. The gene responsible for the aminoglycoside resistance was cloned and sequenced. The deduced amino acid sequence of the resistance gene shared 82% identity with RmtA, which was recently identified as 16S rRNA methylase conferring high-level aminoglycoside resistance in Pseudomonas aeruginosa. Histidine-tagged recombinant protein showed methylation activity against E. coli 16S rRNA. The novel aminoglycoside resistance gene was therefore designated rmtB. The genetic environment of rmtB was further investigated. The sequence immediately upstream of rmtB contained the right end of transposon Tn3, including bla TEM , while an open reading frame possibly encoding a transposase was identified downstream of the gene. This is the first report describing 16S rRNA methylase production in S. marcescens. The aminoglycoside resistance mechanism mediated by production of 16S rRNA methylase and subsequent ribosomal protection used to be confined to aminoglycoside-producing actinomycetes. However, it is now identified among pathogenic bacteria, including Enterobacteriaceae and P. aeruginosa in Japan. This is a cause for concern since other treatment options are often limited in patients requiring highly potent aminoglycosides such as amikacin and tobramycin.

Copper proteins play key roles in biological processes such as electron transfer and dioxygen activation; the active site of each of these proteins is classified as either type 1, 2, or 3, depending on its optical and electron paramagnetic resonance properties. We have built a new type of site that we call “type zero copper” by incorporating leucine, isoleucine, or phenylalanine in place of methionine at position 121 in C112D Pseudomonas aeruginosa azurin. X-ray crystallographic analysis shows that these sites adopt distorted tetrahedral geometries, with an unusually short Cu-O(G45 carbonyl) bond (2.35–2.55 Å). Relatively weak absorption near 800 nm and narrow parallel hyperfine splittings in EPR spectra are the spectroscopic signatures of type zero copper. Copper K-edge x-ray absorption spectra suggest elevated Cu(II) 4p character in the d-electron ground state. Cyclic voltammetric experiments demonstrate that the electron transfer reactivities of type zero azurins are enhanced relative to that of the corresponding type 2 (C112D) protein.

The expression cloning of a cDNA for globotriaosylceramide (Gb3)/CD77 synthase (␣1,4-galactosyltransferase) was achieved using an anti-Gb3 antibody and mouse L cells as a recipient cell line for the transfection. The isolated cDNA clone designated pVTR1 predicted a type II membrane protein with 19 amino acids of cytoplasmic domain, 26 amino acids of transmembrane region, and a catalytic domain with 308 amino acids. Introduction of the cDNA clone into L cells resulted in the neosynthesis of Gb3/CD77, and the extracts of the transfectant cells showed ␣1,4-galactosyltransferase activity only on lactosylceramide and galactosylceramide. In Northern blotting, a 2.3-kilobase mRNA was strongly expressed in heart, kidney, spleen, and placenta and weakly in colon, small intestine, and brain. Transfection of the cDNA into L cells resulted in the constitution of sensitivity to the apoptosis with Shiga-like toxins (verotoxins). Since Gb3/CD77 synthase initiates the synthesis of globo series glycolipids, the isolation of this cDNA will make possible further investigations into the function of its important series of glycolipids.

SummaryHelicobacter pylori infection induces apoptosis in gastric epithelial cells. Here, we report a novel apoptosis-inducing protein that functions as a leading factor in H. pylori -mediated apoptosis induction. We purified the protein from H. pylori by separating fractions that showed apoptosis-inducing activity. This protein induced apoptosis of AGS cells in a dosedependent manner. The purified protein consisted of two protein fragments with molecular masses of about 40 and 22 kDa, which combined to constitute a single complex in their natural form. N-terminal sequencing indicated that both these protein fragments were encoded by the HP1118 gene. The purified protein exhibited g g g g -glutamyl transpeptidase activity, the inhibition of which by 6-diazo-5-oxo-L -norleucine resulted in a complete loss of apoptosis-inducing activity. To the best of our knowledge, the apoptosisinducing function is a newly identified physiological role for bacterial g g g g -glutamyl transpeptidase. The apoptosis-inducing activity of the isogenic mutant g g g gglutamyl transpeptidase-deficient strain was significantly lower compared with that of the parent strain, demonstrating that g g g g -glutamyl transpeptidase plays a significant role in H. pylori -mediated apoptosis. Our findings provide new insights into H. pylori pathogenicity and reveal a novel aspect of the bacterial g g g gglutamyl transpeptidase function.

This paper scrutinises organisational change in Japanese and UK universities which are engaged in entrepreneurial activities. The study focuses on recent changes in governance, management, leadership, and funding in these universities. The paper argues there are convergent trends between Japanese and UK universities in terms of increasing entrepreneurial activities, a review of institutional strategies, a review of the organisation, the application of market-oriented institutional policy, links with the industrial sector, the notion of a public financial crisis and changing external environment, strong leadership of the university President or Vice-Chancellor, and the notion of the accountability of the university to society as a whole. However, the application of particular institutional strategies, entrepreneurial culture, and the way in which an institution relates itself to the private sector significantly differs among institutions. The paper suggests that those differences are related to different institutional history and characteristics -including those between national and private universities in Japan, and old and new universities in the UK -as well as different government policies between Japan and the UK.The paper first proposes a theoretical model for the five types of entrepreneurial culture of the institutions. It then examines the model by using case studies: Nottingham Trent University (UK), University of Surrey (UK), University of Tokyo (Japan), and Waseda University (Japan).