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Cross-linked complex between photosynthetic reaction center and horse heart cytochrome c (cyt c ) was prepared for the control of molecular orientation in Langmuir–Blodgett (LB) method. The surface of cyt c is highly hydrophilic whereas that of RC is hydrophobic. A polar distribution of hydrophobicity/hydrophilicity in the complex was realized by the cross-linkage of the different protein molecules. An index was introduced to evaluate the hydrophobicity of the surface of the proteins. The orientation of RCs in an LB film was evaluated by the displacement current. The complex showed a response 1.5 times larger than that of RC.

Appearance of Edwardsiella tarda were monitored in pond water culturing eel Anguilla japonica in Kagoshima prefecture. E. tarda were isolated at almost all sampling times. Serotype and siderophore production of the E. tarda isolates, which are involved with its pathogenesis, were determined. Out of 370 isolates, 194 isolates (52%) were classified into serotype A and 246 isolates (66%) produced siderophore. Ninety-one percent of the isolates that were classified into serotype A produced siderophore;72%of those that produced siderophore were classified into serotype A. There was no cross linkage between serotype and siderophore production in E. tarda.

Aims Outbreaks of healthcare-associated infection (HCAI) in neonatal units (NNUs) have a significant burden of morbidity and mortality and cause substantial disruption and cost to neonatal networks. The number of NNU HCAI clusters in 2011 in England, their size and causative organisms, were estimated using currently available surveillance tools. Methods Data derived from voluntary laboratory reporting (LabBase 2), national reference laboratories and a Health Protection Agency outbreak reporting tool (HPZone) were searched to identify potential NNU HCAI clusters. The analysis was limited to the most likely causative organisms ( S. aureus , Enterobacter spp., E. coli , Acinetobacter spp., Klebsiella s pp., Pseudomonas spp., Serratia spp.) . Clusters were defined as: (i) any neonatal cluster or outbreak reported in HPZone; (ii) laboratory reports of at least 2 isolates originating from the same hospital and sharing the same VNTR or strain type, with at least one case below the age of 28 days, and with a maximum of 14 days between two cases, and (iii) 2 or more reports of the same infection in neonates in the same hospital in a 14 day period in LabBase. Cross linkage of the 3 data sources was then attempted. Results 116 neonatal clusters including both colonisation and invasive disease were identified, involving at least 666 neonates. 43.4% of the clusters were MRSA, followed by MSSA (26%), E.coli (13%), Enterobacter (12%), and Pseudomonas (10%). There were on average 9.2 neonatal clusters per month (range 0–14). The median number of babies per cluster was 3 (range 2–80). When only bacteraemia samples were considered, E.coli was the most common organism accounting for 57% of clusters. The study likely underestimates the number of clusters due to a lack of standardised reporting. It was not always possible to fully characterise the clusters as formal outbreaks due to data limitations. Conclusion This analysis identified a high number of HCAI clusters in English NNUs. A standardised approach to the definition, reporting, management and surveillance of NNU HCAI outbreaks is required to enable reliable outbreak detection and appropriate action.

Structures of antitumor antibiotics BBM-928 A, B and C have been determined. They are cyclic decadepsipeptides containing 3-hydroxy-6-methoxyquinaldic acid as a chromophore. Two amino acids, not found in nature, L-beta-hydroxyl-N-methylvaline and trans-(3S,4S)-4-hydroxy-2,3,4,5-tetrahydropyridazine-3-carboxylic acid, were identified as structural constituents of the antibiotic. In gross structure, BBM-928 resembles the echinomycin group of antibiotics which are cyclic octadepsipeptides having a quinoxaline chromophore, but BBM-928 differs from the latter group by virtue of the lack of a sulfur-containing cross linkage.

We have compared the proteins from superior cervical sympathetic ganglia (SCSG) in young and old male Fischer rats. We have searched for the kinds of changes in protein size or charge which are predicted by such cellular aging theories as the error catastrophe theory, the somatic mutation theory, the cross-linkage theory, translational aging, the deamidation theory, and the autoimmune theory. SCSG from young (2 months to 1 year) and old (21-24 months) rats were labeled in vitro for 1 h with 14C-leucine prior to protein extraction for analysis. Protein analysis was on high-resolution, two dimensional polyacrylamide gels using O'Farrell's technique, with some modifications. Proteins were separated according to isoelectric point in one dimension and molecular weight in the second dimension. The changes predicted by the above aging theories were detected neither in the staining pattern, showing protein amounts, nor in the labeling pattern on autoradiographs of dried gels, showing newly synthesized proteins. The results suggest the possibility that, at least for rat, some other mechanisms for aging are present.

Coliphage T7 was dissolved in tryptone broth and exposted to 60C gamma-radiation. Cross-linkage of DNA and protein of the virion was assayed using phenol-water countercurrent distribution. The results are interpreted in terms of a statistical model of cross-linkage and double-strand breaks. It was found that protein--DNA cross-links accumulate linearly with dose at a rate of o.74 X 10(-11) cross-links per rad per nucleotide pair, which is of the order of 5 per cent of the formation rate of double-strand breaks.

Penicillin G was found to inhibit the formation of the d -alanyl- l -alanine cross-linkage in intact cells of Micrococcus luteus . This reaction was approximately 50-fold less susceptible to penicillin than the formation of the d -alanyl- l -lysine cross-linkage in the same organism. The presence of two penicillin-susceptible transpeptidation reactions that function in the incorporation of peptidoglycan precursors into the cell wall is proposed.

Cross-linkage of membrane receptors of B cells leads to cellular activation and progress through the G1 phase of the cell cycle. Entry into S phase is generally determined by the action of costimulatory factors. We describe here the cellular biochemical events which result in B cell activation as a result of cross-linkage of membrane receptors and present evidence for a feedback regulatory mechanism which leads to cellular desensitization. We further describe the purification, characterization, and receptor-binding properties of B cell stimulatory factor-1 (BSF-1), a T cell-derived lymphokine whose action is important in B cell entry into S phase. We provide evidence that BSF-1 acts as a cocompetence factor in the growth regulation of B and T lymphocytes and suggest that it acts in a similar manner on all cells of hematopoietic lineage.