What has the UK Ocean Acidification research programme told us? An infographic for Defra.

This is an infographic requested by Defra on the findings of the UK Ocean Acidification research programme

Engineering Dehydrated Amino Acid Residues in the Antimicrobial Peptide Nisin

The small antimicrobial peptide nisin, produced by Lactococcus lactis, contains the uncommon amino acid residues dehydroalanine and dehydrobutyrine and five thio ether bridges. Since these structures are posttranslationally formed from Ser, Thr, and Cys residues, it is feasible to study their role in nisin function and biosynthesis by protein engineering. Here we report the development of an expression system for mutated nisin Z (nisZ) genes, using nisin A producing L. lactis as a host. Replacement by site-directed mutagenesis of the Ser-5 codon in nisZ by a Thr codon, led to a mutant with a dehydrobutyrine instead of a dehydroalanine residue at position 5, as shown by NMR. Its antimicrobial activity was 2-10-fold lower relative to wild-type nisin Z, depending on the indicator strain used. In another mutagenesis study a double mutation was introduced in the nisZ gene by replacing the codons for Met-17 and Gly-18 by codons for Gln and Thr, respectively, as in the third lanthionine ring of the related antimicrobial peptide subtilin from Bacillus subtilis. This resulted in the simultaneous production of two mutant species, one containing a Thr residue and the other containing a dehydrobutyrine residue at position 18, both having different bacteriocidal properties.

Do Action Video Games Improve Perception and Cognition?

Frequent action video game players often outperform non-gamers on measures of perception and cognition, and some studies find that video game practice enhances those abilities. The possibility that video game training transfers broadly to other aspects of cognition is exciting because training on one task rarely improves performance on others. At first glance, the cumulative evidence suggests a strong relationship between gaming experience and other cognitive abilities, but methodological shortcomings call that conclusion into question. We discuss these pitfalls, identify how existing studies succeed or fail in overcoming them, and provide guidelines for more definitive tests of the effects of gaming on cognition

The use of the API 20 NE bacteria classification procedure to identify Pasteurellaceae strains in rodents and rabbits

Forty growth-factor independent Pasteurellaceae strains representing most known taxa from rodents and  rabbits were API 20 NE profiled by four laboratory animal diagnostic laboratories using their routine  methodology. Significant differences were found in the number of bacterial strains classified with the  Pasteurellaceae. The results of the four laboratories taken together showed that 136 (85 %) of the 160 tests  carried out with the 40 strains led to classification with the family. The 23 Pasteurellaceae strains from  species (Pasteurella aerogenes, P. multocida, P. pneumotropica) present in the API 20 NE data base (API  taxa strains) and the 17 strains from taxa not included (non - API taxa strains) were classified with the family  with similar frequency.Pasteurella species designation differed significantly between the laboratories and full agreement in speciation  was found with only 9 (22.5 %) of the 40 strains. Of the tests carried out with P. multocida and P.  pneumotropica, 42 and 52 % respectively led to misclassification. Conversely 38 % of the profiles  obtained with non- API taxa strains led to identification as P. multocida or P. pneumotropica.  We conclude that identification of Pasteurellaceae to the species level by the API 20 NE system is unreliable,  but the system is useful to classify various Pasteurellaceae taxa from rodents and rabbits with the  bacterial family.