Paracoccus pantotrophus NapC can reductively activate cytochrome cd1 nitrite reductase

The oxidized "as isolated" form of Paracoccus pantotrophus cytochrome cd1 nitrite reductase has a bis-histidinyl coordinated c heme and a histidine/tyrosine coordinated d1 heme. This form of the enzyme has previously been shown to be kinetically incompetent. Upon reduction, the coordination of both hemes changes and the enzyme is kinetically activated. Here, we show that P. pantotrophus NapC, a tetraheme c-type cytochrome belonging to a large family of such proteins, is capable of reducing, and hence activating, "as isolated" cytochrome cd1. NapC is the first protein from P. pantotrophus identified as being capable of this activation step and, given the periplasmic co-location and co-expression of the two proteins, is a strong candidate to be a physiological activation partner.     

Amino acid and divalent ion permeability of the pores formed by the Bacillus thuringiensis toxins Cry1Aa and Cry1Ac in insect midgut brush border membrane vesicles

The pores formed by Bacillus thuringiensis insecticidal toxins have been shown to allow the diffusion of a variety of monovalent cations and anions and neutral solutes. To further characterize their ion selectivity, membrane permeability induced by Cry1Aa and Cry1Ac to amino acids (Asp, Glu, Ser, Leu, His, Lys and Arg) and to divalent cations (Mg(2+), Ca(2+) and Ba(2+)) and anions (SO(4)(2-) and phosphate) was analyzed at pH 7.5 and 10.5 with midgut brush border membrane vesicles isolated from Manduca sexta and an osmotic swelling assay. Shifting pH from 7.5 to 10.5 increases the proportion of the more negatively charged species of amino acids and phosphate ions. All amino acids diffused well across the toxin-induced pores, but, except for aspartate and glutamate, amino acid permeability was lower at the higher pH. In the presence of either toxin, membrane permeability was higher for the chloride salts of divalent cations than for the potassium salts of divalent anions. These results clearly indicate that the pores are cation-selective.     

Plant regeneration from protoplasts of Enteromorpha intestinalis (Chlorophyta, Ulvophyceae) as seedstock for macroagal culture

A continuous micropropagation was established from protoplasts of thegreen alga Enteromorpha intestinalis. The effects of two differentcrude enzymes and the osmolarity at different concentrations of the enzymesolution on algal protoplast yields were tested. The optimal enzymecomposition for cell wall digestion and protoplast viability was 2%cellulase R 10 Onozuka and 2% Aplysie with 0.5 m mannitol. Largenumbers of Enteromorpha protoplasts were released (10.0 × 10⁶protoplasts from 1 g fresh thalli) and settled on a rangeof substrata. Regeneration of the protoplasts followed the normal patternfor this species. Conditions for pure cultures and efficient systems offloating supports with nets were determined to optimise the product qualityof plantlets of Enteromorpha. A promising storage process has beendeveloped which involves including protoplasts in beads of alginic acid gel.Plants regenerated from protoplasts may also be used as seedstock tofacilitate propagation for macroalgal culture.     

Preparative resolution of some 5,5-hydantoin derivatives via formation of diastereoisomeric salts

Several preparative resolutions of 5,5-disubstituted hydantoins have been achieved via fractional crystallization of diastereoisomeric salts. The process can be extended by making use of the difference between the variation of solubilities of the hydantoins and their salts with α-methylbenzylamine as a function of the alkalinity of the medium. Optimization for each resolution procedure involves a refinement of the excess amount of base needed. © 1992 Wiley-Liss, Inc.     

Proteomic analysis of cell envelope from Staphylococcus xylosus C2a, a coagulase-negative staphylococcus

Staphylococcus xylosus is a saprophytic bacterium commonly found on skin of mammals but also used for its organoleptic properties in manufacturing of fermented meat products. This bacterium is able to form biofilms and to colonize biotic or abiotic surfaces, processes which are mediated, to a certain extent, by cell-envelope proteins. Thus, the present investigation aimed at evaluating and adapting different existing methods for cell-envelope subproteome analyses of the strain S. xylosus C2a. The protocol selected consisted initially of a lysostaphin treatment producing protoplasts and giving a fraction I enriched in cell wall proteins. A second fraction enriched in membrane proteins was then efficiently recovered by a procedure involving delipidation with a mixture of tributyl phosphate, methanol, and acetone and solubilization with a buffer containing ASB14. Proteins were separated using two-dimensional gel electrophoresis (2-DE) and identified using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). A total of 168 protein spots was identified corresponding to 90 distinct proteins. To categorize and analyze these proteomic data, a rational bioinformatic approach was carried out on proteins identified within cell envelope of S. xylosus C2a. Thirty-four proteins were predicted as membrane-associated with 91% present, as expected, within fraction II enriched in membrane proteins: 24 proteins were predicted as membranal, 3 as lipoproteins, and 7 as components of membrane protein complex. Eighteen out of 25 (72%) proteins predicted as secreted were indeed identified in fraction I enriched in cell wall proteins: 6 proteins were predicted as secreted via Sec translocon, and the remaining 19 proteins were predicted as secreted via unknown secretion system. Eighty-one percent (25/31) of proteins predicted as cytoplasmic were found in fraction II: 8 were clearly predicted as interacting temporarily with membrane components. By coupling conventional 2-DE and bioinformatic analysis, the approach developed allows fractionating, resolving, and analyzing a significant and important set of cell envelope proteins from a coagulase-negative staphylococcus, that is, S. xylosus C2a.     

Possible relationship between H-Y antigen and female gonadogenesis in the Colorado potato beetle,Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

Summary

The Daudi cell line, a male human line from Burkitt's lymphoma, possesses the peculiarity of releasing H-Y antigen into its culture medium. Daudi-conditioned medium was injected into Colorado potato beetles either during the blastoderm stage, when individualization of the pole cells occurs, or later, during gonadal differentiation. Ovarian and testicular sections examined at hatching showed that only ovarian differentiation was affected by the Daudi conditioned medium, which, irrespective of the day of injection, reduced the number of the terminal filaments of the future lateral ovarioles. Furthermore, in some cases sexual differentiation was blocked altogether. When H-Y antigen was precipitated from the conditioned medium with specific H-Y antisera, the effectiveness of Daudi-conditioned medium was partially destroyed. These results suggest that mammalian H-Y antigen inhibits morphogenetic events leading to ovarian differentiation in the Colorado potato beetle.     

Onderwijs in het Nationaal Programma Ouderenzorg

The Netherlands Organisation of Health Research and Development started in 2008 the Dutch National Care for the Elderly Programme (in Dutch abbreviated as NPO) with the aim to improve the quality of life for the frail older people through better quality of care (health, social, community) which is tailored to the needs and wants of older people. The delivery of good care is related with competent professional behaviour which is inextricably linked to the education of professionals. This article presents an overview of 32 educational programmes developed within the NPO. Within the NPO different educational programmes were developed on relevant themes to improve elderly care. However, the programmes focused mainly on professionals in health care, especially those working in primary care. For nurses and nursing assistants and more or less for physicians also different educational programmes were developed. Educational programmes for paramedics or professionals working in social care, housing or in the municipalities were scarce. This is also the case for specific themes in elderly care like loneliness or (domestic) violence. Moreover, none of the experiments focused on older people or informal care givers. Although 22 of the 32 projects developed educational programmes for different groups, multi – or interdisciplinary education is rare in these programmes. Based on the overview we advise the development of more educational programmes on: target groups which were less or not addressed in the NPO, like professionals in social care and paramedics; multi- or interdisciplinary collaboration; and themes, like loneliness in older people and elder abuse.     

Phenotypic determinants of individual fitness in female fur seals: larger is better

Inter-individual differences in fitness in female vertebrates have often been related to phenotypic discrepancies, suggesting that bigger individuals exhibit greater fitness. However, the use of the temporally variable indices of quality, such as body mass/condition, may not represent the most reliable index over longer time intervals. Few studies have assessed the direct influence of body size (BS) on individual fitness. We addressed this knowledge gap using data from long-term monitoring of individually marked female subantarctic fur seals. The females of higher quality (i.e. higher lifetime reproductive success) were larger in BS than their counterparts, which correlated with their ability to provision their pup with greater and more regular energy supply, possibly through the maximization of foraging performance and body fat storage. We accordingly found that our study population could be divided into three contrasted categories of maternal quality, with 33% of the females producing over 71% of the viable offspring constituting the next generation. We suggest that a larger BS represents a crucial selective advantage for a central place forager, especially when exploiting remotely available resources.