As we learn more about terrestrial organisms that thrive in extreme conditions, the possibility for life on other moons and/or planets becomes more intriguing. This study was designed to temporally examine the effects of various extreme conditions, such as ultraviolet radiation and salt concentrations (i.e., NaCl and MgS[O.sub.4]) on the morphological, physiological and biochemical properties of two bacterial types. The responses of Escherichia coli and Bacillus cereus were examined under controlled laboratory conditions for 48 hours using spectrophotometry, viable counts and standard microbiological assays. Overall, the results showed E. coli cells to be more sensitive to UV radiation compared to B. cereus cells. Under varying concentrations of NaCl, it was also found that the cells prefer lower concentrations (5%). The results of this study validate the idea that the survivability of bacterial cells under extreme conditions is probably due to their unique morphological, physiological, and biochemical properties. These results thus contribute to studies of cellular life forms under extreme conditions, as observed on Mars and Europa.
Identification and Inhibition of Bacteria in Automotive Paint Wastewater. Taryn Sabey, and Michelle Ammerman, Kettering University
Biocide use is necessary in paint wastewater treatment to prevent bacterial build-up which can lead to metal corrosion, and plant hygiene issues as well as malodor. The corrosion can cause costly equipment breakdown. Bacteria are also able to form biofilms which will prevent the elimination of excess paint from the water, inhibiting water recycling. Examination of growth inhibition of a mixed microbial sample from waste water using common industrial biocides is being performed in order to determine their relative efficacies at typical processing pH. The biocides being examined include 2,2-dibromo-3-nitrilopropionamide (DBNPA), a combination of 5-chloro-2-methyl-2H-isothiazol-3-one and 2-methyl-2H-isothiazol-3-one (CMIT/M1T), 2-hromo-2-nitro-1,3-propanediol (BNP), and hydrogen peroxide (HP). In order to identify the bacterial species present in the wastewater, the Biolog Gen III MicroLog Manual System is being used for isolated colonies. The information obtained from this study should help to elucidate the most efficient means of treating the wastewater and provide information about the composition of bacterial species in the microbial sample.
Comparison of Colilert and qPCR Methods for Monitoring Inland Lake Beaches in Muskegon County. Brian T. Scull, Richard R. Rediske, and Molly Lane, Grand Valley State University; Brittany Schulz, Wheaton College
A comparison of Colilert 18 and qPCR methods was conducted on 15 inland lake beaches in Muskegon County, Michigan during 2017. Beaches were at lakes with varying trophic status and in rural and urban settings. Beach samples were collected weekly for five weeks at three locations in each lake and composited into a single sample for analysis. Each sample was analyzed by Colilert 18 (EPA 9223B Enzyme Substrate Test) and qPCR (EPA draft Method C: E. coli by qPCR). A comparison of the results from both methods was conducted using the Index of Agreement and other statistical methods. The results of the weekly monitoring and method comparison will be discussed with respect to methodology differences, impact of environmental variables, and compliance with standards for Total Body Contact.
Transposon Mutagenesis to Determine the Basis for Symbiosis-Supported Aerobic Growth between Termite Gut Bacteria. Kimberly A Vreugdenhil and John T Wertz, Calvin College
Termites have complex microbial communities in their guts, partly due to the wide range of niches within it. Some of these microorganisms may be able to survive alone, but there is increasing evidence for extensive cross feeding among them. Two symbiotic bacteria, in particular, have been isolated from the guts of Reticulitermes flavipes. Citrobacter sp. RFC-10 grows and thrives in oxygen, while Dysgonomonas sp. RFCAL-19 only grows in anoxia; however, if the two are grown closely together on solid media, RFCAL-19 is able to grow in the presence of oxygen. We used transposon mutagenesis to determine the genetic basis for this suspected cross feeding. The TN5 Transposon Kit was used to randomly knock out genes of RFC-10, which were then sequenced and run through a database. Of the 1071 mutants created, 30 appeared to not support the growth of RFCAL-19, suggesting that a gene or genes related to the cross-feeding had been interrupted. However, after running the sequences through the NCBI BLAST database, no significant matches were found. Further research and analysis are needed to determine with certainty what genes and proteins are influencing the symbiosis between RFC-10 and RFCAL-19.
A Comparison of qPCR and Colilert Escherichia coli Data at Lake Michigan Beaches in Muskegon County, Michigan. Molly Lane, Richard Rediske, Brian Scull, and Brittany Schulz, Grand Valley State University
A comparison of Colilert 18 and qPCR methods was conducted on three Lake Michigan beaches in Muskegon County during 2016 and 2017. Beaches at Pere Marquette Park, P.J. Hoffmaster State Park Campground, and Meinert Park were sampled weekly for ten weeks at three locations. Each sample was analyzed by Colilert 18 (EPA 9223B Enzyme Substrate Test) and qPCR (EPA draft Method C: E. coli by qPCR). A comparison of the results from both methods was conducted using the Index of Agreement and [R.sup.2]. The weekly monitoring results and method comparison will be discussed with respect to methodology differences, impact of environmental variables, and compliance with standards for Total Body Contact.
Gut Microbiota Incorporation of Clostridium difficile via Coaggregation. Thomas Brewer, Eastern Michigan University
Clostridium difficile is a nosocomial, opportunistic pathogen that costs the United States $3.2 billion every year. However, the same pathogen is capable of inhabiting asymptomatically within the natural gut microbiota. Until now, its interaction with specific microbes is undocumented. Here, interaction is observed via coaggregation, or the interactivity of cells via cell surface molecules.
Clostridium difficile was tested along side members of the Firmicute and Bacteroidetes genera. Hydrophobicity and inhibition assays were also performed to identify the mechanism of interaction. Coaggregating partners were then differentially labeled with fluorescent tags and imaged via confocal microscopy. Tri-partner assays were also performed to assess possible biofilm incorporation. Then, the identified partners were grown together within biofilm growing conditions to observe incorporation of Clostridium difficile cells with gut microbe biofilms.
Results of this research provide insight into the persistence of Clostridium difficile, whether pathogenic or asymptomatic. Identifying its place in the gut microbiota can further influence the effectiveness of fecal transplants as well as artificial microbiota augmentation for prevention of disease. Understanding how these microbes influence each other is a vital step in efficient utilization of the body's second brain, the gut microbiota.
Synergism between Third-Generation Cephalosporins and Phenothiazine Derivatives in Neisseria sicca. Michael Buratovich and Haley Coggins, Spring Arbor University
Chemical derivatives of the parent compound phenothiazine are members of the larger group of psychopharmaceuticals known as first-generation antipsychotics. Previous work in our laboratory has demonstrated that three phenothiazine derivatives, chlorpromazine, chlorprothixene, and thioridazine, have bacteriostatic activity against Neisseria species. The most potent of these phenothiazine derivatives, thioridazine, was tested for synergistic antibacterial activity in combination with third-generation cephalosporins. Specifically, thioridazine was tested in combination with cefdinir, ceftaxime, ceftriaxone, and ceftazidime. A sublethal concentration of thioridazine (10 [micro]g/ml) was combined with varied concentrations of these third generation cephalosporins in standard Minimal Inhibitory Concentration (MIC) tests. In these MIC tests, thioridazine shows synergy with cefdinir, ceftaxime, and ceftriaxone. However, ceftazidime does not show activity against Neisseria sicca either with or without thioridazine. Therefore, thioridazine shows antibacterial synergy with cefdinir, ceftaxime, and ceftriaxone, but not with ceftazidime.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||effects of extraterrestrial environments on bacteria, bacterial control in automotive paint wastewater, inland lake beaches monitoring|
|Date:||Sep 22, 2018|
|Previous Article:||Medieval Studies.|