Next Article in Journal
Genetic Diversity of Black Salamanders (Aneides flavipunctatus) across Watersheds in the Klamath Mountains
Next Article in Special Issue
Preliminary Analysis of Life within a Former Subglacial Lake Sediment in Antarctica
Previous Article in Journal / Special Issue
Untangling the Genetic Basis of Fibrolytic Specialization by Lachnospiraceae and Ruminococcaceae in Diverse Gut Communities
Diversity 2013, 5(3), 641-656; doi:10.3390/d5030641

Examination of a Culturable Microbial Population from the Gastrointestinal Tract of the Wood-Eating Loricariid Catfish Panaque nigrolineatus

1,* , 2
1 Department of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK 2 Departments of Marine Biotechnology and Biological Sciences, University of Maryland Baltimore County, Baltimore, MD 21250, USA 3 Department of Biological Sciences, Towson University, Towson, MD 21252, USA
* Author to whom correspondence should be addressed.
Received: 22 May 2013 / Revised: 2 August 2013 / Accepted: 13 August 2013 / Published: 19 August 2013
(This article belongs to the Special Issue Microbial Ecology and Diversity)
View Full-Text   |   Download PDF [1012 KB, uploaded 19 August 2013]   |   Browse Figures


Fish play a critical role in nutrient cycling and organic matter flow in aquatic environments. However, little is known about the microbial diversity within the gastrointestinal tracts that may be essential in these degradation activities. Panaque nigrolineatus is a loricariid catfish found in the Neotropics that have a rare dietary strategy of consuming large amounts of woody material in its natural environment. As a consequence, the gastrointestinal (GI) tract of P. nigrolineatus is continually exposed to high levels of cellulose and other recalcitrant wood compounds and is, therefore, an attractive, uncharacterized system to study microbial community diversity. Our previous 16S rRNA gene surveys demonstrated that the GI tract microbial community includes phylotypes having the capacity to degrade cellulose and fix molecular nitrogen. In the present study we verify the presence of a resident microbial community by fluorescence microscopy and focus on the cellulose-degrading members by culture-based and 13C-labeled cellulose DNA stable-isotope probing (SIP) approaches. Analysis of GI tract communities generated from anaerobic microcrystalline cellulose enrichment cultures by 16S rRNA gene analysis revealed phylotypes sharing high sequence similarity to known cellulolytic bacteria including Clostridium, Cellulomonas, Bacteroides, Eubacterium and Aeromonas spp. Related bacteria were identified in the SIP community, which also included nitrogen-fixing Azospirillum spp. Our ability to enrich for specialized cellulose-degrading communities suggests that the P. nigrolineatus GI tract provides a favorable environment for this activity and these communities may be involved in providing assimilable carbon under challenging dietary conditions.
Keywords: microbial diversity; cellulose degradation; enrichment; Panaque; gastrointestinal tract microbial diversity; cellulose degradation; enrichment; Panaque; gastrointestinal tract
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Share & Cite This Article

Further Mendeley | CiteULike
Export to BibTeX |
MDPI and ACS Style

Watts, J.E.M.; McDonald, R.; Daniel, R.; Schreier, H.J. Examination of a Culturable Microbial Population from the Gastrointestinal Tract of the Wood-Eating Loricariid Catfish Panaque nigrolineatus. Diversity 2013, 5, 641-656.

View more citation formats

Article Metrics

For more information on the journal, click here


Cited By

[Return to top]
Diversity EISSN 1424-2818 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert