University of Saskatchewan

Western College of Veterinary Medicine

Schellenberg, John

Post-Doctoral Fellow
Veterinary Microbiology
Office Location: WCVM 1241
Phone: 306-966-6299
Fax: 306-966-7244
Email: jos032@mail.usask.ca


Academic Credentials


Research Interests

2010-2013: Post-doctoral fellow, Dept. of Microbiology, University of Manitoba. Research focus: Genomics, transcriptomics and proteomics of ethanol-producing, thermophilic clostridia in anaerobic co-culture
2014-current: Post-doctoral fellow, WCVM, University of Saskatchewan. Research focus: Molecular and culture-based characterization of novel Gardnerella subgroups in the vaginal microbiota.

Dr. Schellenberg began his graduate work studying the ability of Lactobacillus, Streptococcus, and Bifidobacterium strains to inhibit methicillin-resistant Staphylococcus aureus, developing a novel method using immunofluorescent flow cytometry to track different populations of organisms in mixed anaerobic culture. His PhD work focussed on defining vaginal microbiota in a group of commercial sex workers from Nairobi, Kenya, many of whom never become infected with HIV despite years of exposure, using a combination of culture-based and emerging molecular techniques. These included: 1) phenotyping of isolates on chromogenic culture medium and "finger-printing" using 16S-23S ribosomal interspacer analysis, 2) flow cytometric enumeration of different cell types, and 3) molecular characterization based on the chaperonin-60 universal target (cpn60 UT) in clone libraries and by deep sequencing. His first post-doctoral fellowship focussed on developing "designer co-cultures" of ethanologenic clostridia for improved production of biofuels from lignocellulose such as wheat straw. His efforts included whole-genome sequencing and expression profiling of the type strain of Clostridium stercorarium DSM8532, as well as the development of cpn60 UT-based primers and probes for quantitative PCR to simultaneously track three clostridial sub-populations in mixed culture. The goal of his current research at WCVM is to understand how different subgroups of vaginal Gardnerella contribute to negative reproductive health outcomes, including pre-term birth and HIV infection. Long-term research interests include the influence of acid and peroxide production by intestinal and vaginal organisms on mucosal inflammation, as well as novel visualization techniques for large genomics and expression (transcriptomics/proteomics) datasets.


Publications

SCHELLENBERG, J.J., T.J. Dumonceaux, J.E. Hill, J. Kimani, W. Jaoko, C. Wachihi, J.N. Mungai, M. Lane, K.R. Fowke, T.B. Ball, F.A. Plummer. 2012. Selection, phenotyping and identification of candidate probiotic bacteria from vaginal samples of Canadian and East African women. PLoS One, 7(7):e41217. PMID: 22844440.

Paramel Jayaprakash, T., J.J. SCHELLENBERG, J. Hill. 2012. Resolution and characterization of distinct cpn60-based subgroups of Gardnerella vaginalis in the vaginal microbiota. PLoS One, 7(8):e43009. PMID: 22900080.

Ronan, P.,  C.W. Yeung, J. SCHELLENBERG, G.M. Wolfaardt, M. Hausner. 2012. A versatile and robust aerotolerant microbial community capable of cellulosic ethanol production. Bioresource Tech, 129(156-63).  PMID: 23238345.

SCHELLENBERG, J.J., F.A, Plummer. 2012. The microbiological context of HIV resistance: Vaginal microbiota and mucosal inflammation at the viral point of entry. Int J Inflamm. 131243. PMID: 22506135.

SCHELLENBERG J.J., C.M. Card, T.B. Ball, J.N. Mungai, E. Irungu, J. Kimani, W. Jaoko, C. Wachihi, K.R. Fowke, F.A. Plummer. 2012. Bacterial vaginosis, HIV serostatus and T cell subset distribution in a cohort of East African commercial sex workers: retrospective analysis. AIDS. 26(3), 387-393. PMID: 22095193.

SCHELLENBERG, J.J., M.G. Links, J.E. Hill, T.J. Dumonceaux, J. Kimani, W. Jaoko, C. Wachihi, J.N. Mungai, G.A. Peters, S. Tyler, M. Graham, A. Severini, K.R. Fowke, T.B. Ball, F.A. Plummer. 2011. Molecular definition of vaginal microbiota in East African commercial sex workers. Appl Environ Microbiol. Jun;77(12):4066-74. PMID: 21531840.

Dumonceaux, T.J., J. SCHELLENBERG, V. Goleski, J.E. Hill, W. Jaoko, J. Kimani, D. Money,  T.B. Ball, F.A. Plummer, A. Severini. 2009. Multiplex detection of bacteria associated with normal microbiota and with bacterial vaginosis in vaginal swabs by use of oliognucleotide-coupled fluorescent microspheres. J Clin Micro. 47(12): 4067-77. PMID: 19794034.

SCHELLENBERG, J., M.G. Links, J.E. Hill, T.J. Dumonceaux, G.A. Peters, S. Tyler, T.B. Ball, A. Severini, F.A. Plummer. 2009. Pyrosequencing of the chaperonin-60 universal target as a tool for determining microbial community composition. Appl Env Microbiol. 75(9):2889-2898. PMID: 19270139.

SCHELLENBERG, J., T.B. Ball, M. Lane, M. Cheang, F.A. Plummer. 2008. Flow cytometric quantification of bacteria in vaginal swab samples self-collected by adolescents attending a gynecology clinic. J Microbiol Meth. 73(3): 216-26. PMID: 18423913.

SCHELLENBERG. J., W. Smoragiewicz, B. Karska-Wysocki. 2006. A rapid method combining immunofluorescence and flow cytometry for improved understanding of competitive interactions between lactic acid bacteria (LAB) and methicillin-resistant S. aureus (MRSA) in mixed culture. J  Microbiol Meth. 65(1):1-9. PMID: 16154216.