The amino acid sequence of chick skin collagen α1-CB7: The presence of a previously unrecognized triplet

Because alignment of the amino acid sequences of chick skin collagen α2-CB3 (1) with the relevant portion of chick skin collagen α1-CB7 (2) suggested that a Gly-X-Y triplet may have been missed in the latter, the peptide TM-2, produced by tryptic digestion of maleylated α1-CB7, was reinvestigated. Cleavage by trypsin at the unblocked lysine at position 18, and isolation of the resulting COOH-terminal peptide, showed this to be a 15-residue peptide containing a previously unrecognized Gly-Pro-Hyp triplet. Sequencing of the peptide showed this to occupy positions 4 through 6, or 56 through 58 of α1-CB7. The latter thus has 271 instead of 268 residues, and the α1[I] chain 1055 instead of 1052.     

Copper induced oxidation of serotonin: analysis of products and toxicity

Serotonin is a major neurotransmitter that controls many functions, ranging from mood and behaviour through to sleep and motor functions. The non-enzymatic oxidation of serotonin is of significant importance as some oxidation products are considered to be neurotoxic. An interaction between copper and serotonin has been suggested by symptoms observed in a number of neurodegenerative diseases such as Wilson's and Prion diseases. Using PC12 cells as a model of neuronal cells, we show that the interaction between copper and serotonin is toxic to undifferentiated cells. The toxicity is largely due to reactive oxygen species as cell death is significantly reduced in the presence of the antioxidant mannitol. Differentiation of the PC12 cells also confers resistance to the oxidative process. In vitro oxidation of serotonin by copper results in the eventual formation of a coloured pigment, thought to be a melanin-like polymeric species. Using spectroscopic methods we provide evidence for the formation of a single intermediate product. This dimeric intermediate was identified and characterized as 5,5'-dihydroxy-4,4'-bitryptamine. These results indicate that copper structurally alters serotonin and this process may play a role in copper related neurodegenerative diseases.     

LIMaS: the JAVA-based application and database for microarray experiment tracking

Microarrays allow monitoring of gene expression for tens of thousands of genes in parallel and are being used routinely to generate huge amounts of valuable data. Handling and analysis of such data are becoming major bottlenecks in the utilization of the technology. To enable the researcher to interpret the results postanalysis, we have developed a laboratory information management system for microarrays (LIMaS) with an n-tier Java front-end and relational database to record and manage large-scale expression data preanalysis. This system enables the laboratory to replace the paper trail with an efficient and fully customizable interface giving it the ability to adapt to any working practice, e.g., handling many resources used to form many products (chaining of resources). The ability to define sets of activities, resources, and workflows makes LIMaS MIAME-supportive.LIMaS is available for download at (http://www.mgu.har.mrc.ac.uk/microarray.)     

Constraints to growth of annual nettle (Urtica urens) in an elevated CO2 atmosphere: Decreased leaf area ratio and tissue N cannot be explained by ontogenetic drift or mineral N supply

Plant sterols differ from cholesterol in having an alkyl group at Δ-24, and, in the case of stigmasterol, also a Δ-22 double bond. The effects of 10 mol% of three plant sterols (campesterol, β -sitosterol, stigmasterol) and cholesterol on the molecular dynamics and phase behavior in multilamellar liposomes made from different phosphatidylcholine (PC) molecular species have been compared, utilizing the fluorescent probe Laurdan (2-dimethyl-amino-6-laurylnaphthalene). Laurdan reports the molecular mobility in the hydrophilic/hydrophobic interface of the membrane by determining the rate of dipolar relaxation of water molecules close to the glycerol backbone of PC. Our results showed that the Δ-24 alkyl group of plant sterols did not affect their ability to reduce molecular mobility in this region of the PC membranes. However, the plant sterols had a decreased capacity compared to cholesterol to inhibit formation of co-existing domains of gel and liquid-crystalline phases in membranes composed of equimolar dilauroyl-PC and dipalmitoyl-PC. The Δ-22 double bond present in stigmasterol decreased the ability of this sterol, compared to the other phytosterols, to reduce the molecular mobility at the hydrophobic/hydrophilic interface in membranes made of a saturated PC molecular species. However, in membranes made from 16:0/18:2-PC, a lipid species common in plant plasma membranes, stigmasterol was as efficient as other sterols in affecting the polarity and molecular mobility at the hydrophilic/hydrophobic interface of the membrane at 25°C, but was, in contrast to the other sterols, without effect at 0°C. Our results thus confirm as well as contradict the results of previous studies of the interactions between saturated PC and sterols, where other membrane regions were probed. The physiological relevance of the findings is discussed.     

Seasonal Variation of Antifouling Activities of Marine Algae from the Brittany Coast (France)

The antifouling activity of extracts (aqueous, ethanol, and dichloromethane) of 9 marine macroalgae against bacteria, fungi, diatoms, macroalgal spores, mussel phenoloxidase activity, and barnacle cypris larvae has been investigated in relation to season in bimonthly samples from the Bay of Concarneau (France). Of the extracts tested, 48.2% were active against at least one of the fouling organisms, and of these extracts, 31.2% were seasonally active with a peak of activity in summer corresponding to maximal values for water temperature, light intensity, and fouling pressure, and 17% were active throughout the year. This seasonal activity may be adaptive as it coincides with maximal fouling pressure in the Bay of Concarneau. Dichloromethane extracts of Rhodophyceae were the most active in the antifouling assays.     

A Case Study in Serendipity: Environmental Researchers Use of Traditional and Social Media for Dissemination

In the face of demands for researchers to engage more actively with a wider range of publics and to capture different kinds of research impacts and engagements, we explored the ways a small number of environmental researchers use traditional and social media to disseminate research. A questionnaire was developed to investigate the impact of different media as a tool to broker contact between researchers and a variety of different stakeholders (for example, publics, other researchers, policymakers, journalists) as well as how researchers perceive that their use of these media has changed over the past five years. The questionnaire was sent to 504 researchers whose work had featured in a policy-oriented e-news service. 149 valid responses were received (29%). Coverage in traditional media (newspapers, broadcast) not only brokers contact with other journalists, but is a good source of contact from other researchers (n=47, 62%) and members of the public (n=36, 26%). Although the use of social media was limited amongst our sample, it did broker contact with other researchers (n=17, 47%) and the public (n=10, 28%). Nevertheless, few environmental researchers were actively using social media to disseminate their research findings, with many continuing to rely on academic journals and face-to-face communication to reach both academic and public audiences.