5^th Global Congress on Environmental Microbiology November 28-30, 2016 Atlanta, Georgia, USA

Biography:

Kostas Konstantinidis has joined the Faculty at Georgia Tech in November 2007 and he is holding the Carlton S. Wilder Junior Professorship in Environmental Engineering since September 2012. He has earned his BS (1999) in Agriculture Sciences from the Aristotle University of Thessaloniki, Greece and his PhD (2004) from the Center for Microbial Ecology at Michigan State University, where he was a Bouyoukos Fellow. Prior to joining Georgia Tech, he was a Postdoctoral Fellow in the Department of Civil and Environmental Engineering at the Massachusetts Institute of Technology. His education and research interests are at the interface of environmental microbiology with engineering, genomics and computational biology. The overarching goal of his research is to broaden our understanding of the genetic and metabolic diversity of the smallest organisms on the planet, the bacteria and archaea and the role of this diversity for ecosystem function and resilience to natural as well as anthropogenic perturbations. He is also interested in the biotechnological applications of microbial diversity in the bioremediation of environmental pollutants and the assessment of water quality. 

Abstract:

Whether disinfectant exposure promotes antibiotic resistance (Ab^R) has been a long debate with major practical consequences. To obtain insights into this issue, we exposed a microbial community originating from River sediment (Calcasieu River, USA) to benzalkonium chlorides (BAC; a family of quaternary ammonium disinfectants) for 3 years in a fed-batch bioreactor receiving Dextrin Peptone plus BAC as the sole carbon source (DPB bioeractor). A bioreactor receiving only Dextrin Peptone (DP) served as control. Bacterial isolates, representing the same ancestral population in the original inoculum were also obtained from both bioreactors and used to study adaptive evolution in response to increasingly higher BAC concentrations. Metagenomics of the bioreactors and genetic manipulation of isolates revealed that BAC exposure induced the spread of Ab^R in several species via horizontal transfer of mobile DNA elements that encode a BAC efflux pump together with Ab^R genes. Although several BAC-exposed isolates exhibited higher resistance to certain antibiotics, others did not, presumably due to their intrinsic resistance mechanisms. Nonetheless, genomics and transcriptomics analysis of Pseudomonas aeruginosa isolates revealed several fixed mutations in BAC-evolved populations such as in the histidine kinase A domain of the pmrB, which regulates resistance to polymyxin B, consistent with higher MIC values for polymyxin B and the overexpression of genes regulating tetracycline and ciprofloxacin resistance in response to BAC exposure. Collectively, this result revealed that there is a significant link between disinfectants and Ab^R antibiotics, providing new insights into the long-standing debate and have implications for biotechnological solutions to this problem.

Biography:

Reetika Dawar has completed her MD in Microbiology from Kasturba Medical College, Manipal in 2001. As a Clinical Microbiologist she has worked in the field of Bacteriology especially salmonellosis, anaerobes, enteric pathogens, conventional and molecular diagnostic tests, antibiotic resistance, mycobacteriology, mycology, immunoassays for infectious diseases and autoimmune diseases, dengue virus diagnostics and allergy testing. During her tenure for the last 10 years at Indraprastha Apollo Hospitals she has been instrumental in organizing several microbiology workshops and conferences as an Executive Member of the Indian Association of Medical Microbiologists-Delhi Chapter. She has been actively involved in teaching DNB and Diploma in Laboratory Technology students. She has 20 publications in various international journals and several presentations in medical microbiology conferences.

Abstract:

Biography:

Swagata Karmakar is currently pursuing her PhD in Environmental Studies from University of Delhi and completed Master’s degree in Environment Management. She has published two papers in reputed journals and presented her work at many national and international conferences.

Abstract:

Microbial inoculation technologies are being used for enrichment and mobilization of nutrients, remediation of contaminants and increasing the plant growth in stressed and degraded habitats. Such technologies have not given the desired results in many environments as the ecological performance of microbial communities is the net result of a complex interaction among different community members. Phage-bacterium interaction is one of the important biological interactions, which not only shape the microbial community, affect the fitness of microbial population but also affect population density and community functions. The lytic phages kill their host and affect the density, whereas, the temperate phages live inside the bacterial host for a long time before the onset of lysis and therefore, affect the function of host bacteria. However, little is known about the pattern of distribution of bacteria and their associated phages in the environment. Such interactions in a heterogeneous environment, like soil characterized by patchy distribution of nutrients, organic matter, minerals, pH, soil type, and texture are likely to significantly affect the pattern of phage-bacterium distribution. A better understanding of such heterogeneity and its impact on phage-bacterial distribution would provide baseline data to understand structure and function of microbial communities in soil environment. Therefore, in the present study spatial pattern of distribution of phages and bacteria at microscale were examined and factors responsible for such pattern are also analyzed. A detailed analysis of such pattern in different soil types and ecosystems will help in improvement in the efficacy of microbial technologies for diverse soil environment.

Biography:

Christopher Nwankwo is a second year Ph.D. student of the University of Edinburgh, Institute of Quantitative Biology, Biochemistry and Biotechnology. Christopher studied Microbiology at the University of Ilorin, Nigeria and has completed his Masters degree in Biotechnology at the University of Edinburgh. He has major interests in Environmental & Industrial Microbiology using modern biotechnology and molecular biology approaches for the detection of environmental toxins in drinking water and clinical samples.

Abstract:

More than 100 million people globally are estimated to be affected by groundwater contaminated with arsenic, with Bangladesh, West Bengal and Taiwan being the worst hit. Heavy metals play significant roles in the growth and development of living organisms, but when in elevated concentrations, can be lethal due to their interference with normal biological processes. Drinking water available to the growing world population is constantly contaminated by natural and anthropogenic sources which pose serious threat to human lives. The traditional laboratory-based analytical investigations for environmental contaminants are expensive, laborious and usually require trained staff and sophisticated facilities. A disposable, inexpensive, simple and accurate device is necessary for detecting environmental toxins in water and urine which is the aim of this research. This work analyses the reliability of whole-cell biosensor systems for detecting environmental toxins in water and urine. Arsenate level below 10 ppb was detected using a pre-existing arsenic biosensor with stationary overnight incubation. The arsenic biosensor was tested in artificial urine medium and was found to detect arsenic concentration below 10 ppb. Air-dried and freeze-dried cells of the arsenic biosensor stored for 120 days at room temperature and resuspended in sensor medium were also tested and found to detect arsenic concentration below 10 ppb. A novel zinc biosensor was constructed using recombinant E. coli JM109 transformed with plasmids with copies of endogenous zinc-binding transcription factor, ZntR, using lacZ'α as a reporter. The Zn biosensor accurately detected zinc concentrations below the recommended WHO limit of 0.046 mM. For practical reasons, it was also desired to incorporate a coliform assay into biosensor devices to allow simultaneous monitoring of microbial and chemical quality of water. Coliforms were readily detected based on lactose fermentation using a variant of the same growth medium used for biosensor organisms to allow for easy generation of a combined coliform/metal sensor device. Further work aims at developing cheap, simple, accurate and disposable combined biosensors for detection of environmental toxins in water and urine.

Biography:

Asmaa Agoussar has completed his Master’s degree from Cadi Ayyad University and she is currently pursuing her second Master’s degree from University of Montreal, Canada.

Abstract:

Introduction: In Quebec, vegetable crops occupy about 50914 hectares. Several pesticides are used in these cultures and these products pose risks to human health and the environment. According to studies done in Quebec in 2001, 49% of private wells near the potato crop fields have been found contaminated by pesticides.

Hypothesis: The repeated contamination of pesticides to the soil stimulates the growth of microorganisms able of degrading.

Aim: The objective is to identify microbiological variables responsible for the degradation of pesticides in the process of bioremediation using bio-filters and specifically to identify microorganisms capable of growing in soil treated with pesticides, confirm their in vitro ability to degrade pesticides and confirm in situ potential inoculation of the biofilter at the farm.

Methods : • DNA extraction from soil using commercial kits

• Illumina MiSeq 16S rRNA sequencing for microbiome analysis

• Standard bioinformatics analysis of MiSeq data

• Isolation/screening of strains from soil samples to isolate potential pesticide degraders; growth characterization on standard minimal media with pesticides

• Genomic characterization of isolated strains by 16S rRNA sequence analysis

• Pesticide degradation potential analysis by in vitro growth and HPLC analysis   of culture supernatants

Results: Illumina sequencing results showed that the Proteobacteria and Firmicutes are the two most in soil treated with pesticides groups. After in vitro confirm their ability to degrade pesticides, these microorganisms will serve as inoculum for testing in the field using sterile biofilters, then treated with different concentrations of pesticides.

Conclusion: The results of this project will help to adopt a new strategy to reduce the contamination of water resources and improve the quality of aquatic ecosystems and irrigated crops.