Culturing, Diagnostic, and Genetic Manipulation of Spirochetes

TOPICAL COLLECTIONS

Guest Editors

Christopher Pappas

Manhattanville College, Division of Natural Science, Mathematics, and Computing, New York

Dr. Pappas is a Professor of Biology and the Chair of the Division of Natural Science, Mathematics, and Computing at Manhattanville College, located in New York City. His research interests have focused on the spirochetes Borrelia burgodorferi and Leptospira spp., which has resulted in publications related to novel genetic manipulation techniques, carbohydrate utilization, and bacterial gene expression and adaptation throughout the enzootic cycle. The overarching goal of his current research program at Manhattanville is to address questions related to how Leptospira survive outside of the mammalian host for extended periods in abiotic environments.

Melissa J. Caimano

University of Connecticut Health, Department of Medicine

Dr. Melissa Caimano received her Bachelor of Science degree in Microbiology from the University of Rhode Island and her PhD from the University of Alabama at Birmingham, focusing on the genetic elements involved in Streptococcus pneumoniae capsule biosynthesis. She is currently an Assistant Professor in the University of Connecticut Health, Department of Medicine. For more than two decades, she has been engaged in spirochete research, working with four pathogenic species, Borrelia burgdorferi, Treponema denticola, T. pallidum and Leptospira interrogans. The overarching goals of her research include: (i) gene regulation in response to host-specific signals; (ii) structure and function of spirochetal membrane proteins; and (iii) identification of spirochetal gene products required to infect and persist in mammals. She has co-authored more than 90 peer-reviewed papers related to microbial pathogenesis and her work has been funded by multiple NIH- and foundation-funded grants. She also serves on the Editorial Boards of journals such as Infection and Immunity, PLoS Neglected Tropical Diseases and BMC-Infectious Diseases.

Collection Overview

Spirochetes are diderm (i.e., double-membraned) bacteria within the Phylum Spirochaetes. Spirochetes are distinguished by their long, slender appearance (up to 500 μm in length and 0.09 to 3 μm diameter) and their periplasmic flagellar organelles, which together enable them to move rapidly through highly viscous environments penetrate a wide range of tissues. The class Spirochaetia currently consists of 14 genera, 4 orders and 5 families. Several spirochetal genera are of high public health interest, as they include species associated with diseases in humans and animals. Borrelia spp., the etiologic agents of Borreliosis/Lyme disease and relapsing fever, are maintained in nature as part of enzootic cycles that involve mammalian reservoir hosts and either a hard or soft tick vector, respectively. Brachyspira spp., which cause intestinal spirochetosis, and pathogenic Leptospira spp., the etiologic agent of leptospirosis, are transmitted between hosts typically via contaminated soil and water. Oral Treponema spp. are associated with polymicrobial periodontal disease, while T. pallidum subspecies are the causative agents of syphilis, bejel and yaws.

In general, spirochetes are moderate to extreme auxotrophs, acquiring most of their essential nutrients from their surroundings. The study of spirochetes has historically been limited due to their fastidious culturing requirements in addition to slow growth, as well as limited genetic manipulation capabilities within many of these genera. The goal of this collection is to highlight and demonstrate contemporary culturing methods of spirochetes (e.g.- in vitro culturing of Treponema), in addition to visualizing the methodologies currently used to genetically manipulate and diagnose bacteria within the Phylum (e.g.- development of novel diagnostic tools for Leptospira infection, or gene disruption within Borrelia spp.). In addition, bioinformatics, and data analysis techniques (e.g.- NGS) used for the study of spirochetes research will also be considered for the collection.