Structural and biochemical characterization of the exopolysaccharide deacetylase Agd3 required for Aspergillus fumigatus biofilm formation

The exopolysaccharide galactosaminogalactan (GAG) is an important virulence factor of the fungal pathogen Aspergillus fumigatus. Deletion of a gene encoding a putative deacetylase, Agd3, leads to defects in GAG deacetylation, biofilm formation, and virulence. Here, we show that Agd3 deacetylates GAG in a metal-dependent manner, and is the founding member of carbohydrate esterase family CE18. The active site is formed by four catalytic motifs that are essential for activity. The structure of Agd3 includes an elongated substrate-binding cleft formed by a carbohydrate binding module (CBM) that is the founding member of CBM family 87. Agd3 homologues are encoded in previously unidentified putative bacterial exopolysaccharide biosynthetic operons and in other fungal genomes. The exopolysaccharide galactosaminogalactan (GAG) is an important virulence factor of the fungal pathogen Aspergillus fumigatus. Here, the authors study an A. fumigatus enzyme that deacetylates GAG in a metal-dependent manner and constitutes a founding member of a new carbohydrate esterase family.Bio-organic Synthesi

A multicenter controlled trial on knowledge and attitude about cardiopulmonary resuscitation among secondary school children in Malaysia.

BACKGROUND We performed a multicenter controlled trial to assess the knowledge and attitude (KA) about cardiopulmonary resuscitation (CPR) among secondary school children in a district in Malaysia. METHODS This was a prospective intervention study. The primary endpoint of the study was to determine the level of KA about resuscitation after CPR training. The six schools and classes from selected schools were chosen by randomization among the form three and four classes using sealed envelopes. A fully validated questionnaire consisting of three sections (sociodemographic, knowledge and attitude) was given to the pupils before and 2 weeks after the intervention. The intervention group was given a lecture, video show, pamphlet and 1-h practical session on CPR training. The control group received a placebo in order to overcome the learning effect. The maximum scores for the knowledge and attitude sections were 72 and 28, respectively. Repeated measures ANOVA analysis was used for specific objectives to determine the changes in knowledge and attitude level pre- and post-intervention for both study groups. P-values less than 0.05 were taken as significant at 95% confidence intervals. RESULTS The mean (SD) total knowledge scores for the intervention (n = 216) and control (n = 252) groups were 62.43 (13.68) and 62.29 (12.11), respectively (maximum score 72) (p > 0.05). On the other hand, the mean (SD) total attitude scores for the intervention and the control groups were 19.33 (4.51) and 17.85 (4.52), respectively (maximum score 28) (p < 0.001). There were significant differences in mean knowledge and attitude scores between the intervention and control groups with regard to time (pre- and post-intervention). The mean difference in knowledge and attitude scores between both study groups was 8.31 (p < 0.001) and 2.39 (p < 0.001), respectively. CONCLUSIONS The level of knowledge and attitudes of secondary school children was shown to be acceptable prior to the intervention. Furthermore, a brief CPR training program improved their level of knowledge and attitudes significantly as compared to those who had never been trained