July 2016

Event Date: 
Tuesday, July 26, 2016 - 19:00 - 19:45
Institution: 
Macquarie University
Title: 

Functional genomic analyses of multidrug efflux pumps in Acinetobacter baumannii

Abstract: 

Acinetobacter baumannii is a tenacious Gram-negative opportunistic human pathogen, which has become a serious problem in hospital settings, due largely to its high level of drug resistance, and virulence potential.  Bioinformatic analyses using the Transporter Automatic Annotation Pipeline (www.membranetransport.org), maintained by our research group, have identified an abundance of putative multidrug efflux systems in A. baumannii strains. Multidrug efflux pumps have important roles in drug resistance and virulence in a number of Gram-negative pathogens, yet the functional roles of most putative efflux pumps in A. baumannii have not been described. We have undertaken multifaceted global analyses to determine whether the putative efflux pumps are likely to contribute to antimicrobial resistance A. baumannii. Through these analyses we have identified several pumps that mediate the efflux of drugs, including a new family of multidrug efflux pumps, as well as pumps that maintain stable cellular physiology, such as metal ion homeostasis systems. This short talk will focus on our recent work using transposon directed insertion site sequencing to investigate the antimicrobial transport activities of efflux pumps in A. baumannii.

Event Date: 
Tuesday, July 26, 2016 - 18:15 - 18:30
Institution: 
UTS
Title: 

Eletrochemcial Micro-Sensors and their Application in Environmental Research

Event Date: 
Tuesday, July 26, 2016 - 18:00 - 18:15
Institution: 
UNSW
Title: 

Chlorinated ethene degrading bioreactor performance

Abstract: 

This work focuses on the development of trichloroethylene anaerobic degrading consortium and its molecular biology analysis. Subsequently, through acclimating the anaerobic sludge, a TCE-degrading consortium was enriched in the up-flow anaerobic sludge blanket (UASB) reactor. When TCE concentration was 14.6-73mg/L, the TCE removal efficiencies was 85%-90%. The structure of TCE-degrading consortium was analysed by pyrosequencing and 16S rDNA clone library. Many kinds of fermentation bacteria (such as Petrimonas, Clostridium, Enterobacter and Lactococcus) and Methanosaeta (99.54%) that used acetate as sole carbon source were observed. Importantly, there were three types of dechlorinating bacteria: Dehalobacter, Dehalococcoides, and Geobacter. In addition, we found there was Mesotoga prima MesG1.Ag.4.2 in the consortium which was isolated from a polychlorinated biphenyl (PCB)-dechlorinating enrichment culture from Baltimore Harbor sediments and had a reductive dehalogenase gene-a key enzyme in dehalorespiration. By using Central Composite Design in Response Surface Methodology, the growth conditions of the TCE-degrading consortium were optimised. After optimization, the average removal rate of TCE was 97.71%. In addition, the changes of bacterial diversity and community structure and function were studied by high-throughput sequencing under different operation parameters (hydraulic retention time (HRT), temperature, and pH). The results indicated that the order of effect of operation parameters on the bacterial structure and relative abundance was pH>HRT>T.