scholarly journals Census of the Bacterial Community of the Gypsy Moth Larval Midgut by Using Culturing and Culture-Independent Methods

2004 ◽  
Vol 70 (1) ◽  
pp. 293-300 ◽  
Author(s):  
Nichole A. Broderick ◽  
Kenneth F. Raffa ◽  
Robert M. Goodman ◽  
Jo Handelsman
Keyword(s):  
Bacterial Community ◽  
16S Rrna ◽  
Gypsy Moth ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Composition Analysis ◽  
White Oak ◽  
Microbial Composition ◽  
Larval Midgut ◽  
Culture Independent

ABSTRACT Little is known about bacteria associated with Lepidoptera, the large group of mostly phytophagous insects comprising the moths and butterflies. We inventoried the larval midgut bacteria of a polyphagous foliivore, the gypsy moth (Lymantria dispar L.), whose gut is highly alkaline, by using traditional culturing and culture-independent methods. We also examined the effects of diet on microbial composition. Analysis of individual third-instar larvae revealed a high degree of similarity of microbial composition among insects fed on the same diet. DNA sequence analysis indicated that most of the PCR-amplified 16S rRNA genes belong to the γ-Proteobacteria and low G+C gram-positive divisions and that the cultured members represented more than half of the phylotypes identified. Less frequently detected taxa included members of the α-Proteobacterium, Actinobacterium, and Cytophaga/Flexibacter/Bacteroides divisions. The 16S rRNA gene sequences from 7 of the 15 cultured organisms and 8 of the 9 sequences identified by PCR amplification diverged from previously reported bacterial sequences. The microbial composition of midguts differed substantially among larvae feeding on a sterilized artificial diet, aspen, larch, white oak, or willow. 16S rRNA analysis of cultured isolates indicated that an Enterococcus species and culture-independent analysis indicated that an Entbacter sp. were both present in all larvae, regardless of the feeding substrate; the sequences of these two phylotypes varied less than 1% among individual insects. These results provide the first comprehensive description of the microbial diversity of a lepidopteran midgut and demonstrate that the plant species in the diet influences the composition of the gut bacterial community.

scholarly journals Spatial and Temporal Analysis of the Microbial Community in Slow Sand Filters Used for Treating Horticultural Irrigation Water

2003 ◽  
Vol 69 (4) ◽  
pp. 2116-2125 ◽  
Author(s):  
Leo A. Calvo-Bado ◽  
Tim R. Pettitt ◽  
Nick Parsons ◽  
Geoff M. Petch ◽  
J. Alun W. Morgan ◽  
...  
Keyword(s):  
Microbial Community ◽  
Bacterial Community ◽  
16S Rrna ◽  
Plant Pathogen ◽  
Temporal Structure ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Global Changes ◽  
Rrna Gene ◽  
Microbial Composition

ABSTRACT An experimental slow sand filter (SSF) was constructed to study the spatial and temporal structure of a bacterial community suppressive to an oomycete plant pathogen, Phytophthora cryptogea. Passage of water through the mature sand column resulted in complete removal of zoospores of the plant pathogen. To monitor global changes in the microbial community, bacterial and fungal numbers were estimated on selective media, direct viable counts of fungal spores were made, and the ATP content was measured. PCR amplification of 16S rRNA genes and denaturing gradient gel electrophoresis (DGGE) were used to study the dynamics of the bacterial community in detail. The top layer (1 cm) of the SSF column was dominated by a variable and active microbial population, whereas the middle (50 cm) and bottom (80 cm) layers were dominated by less active and diverse bacterial populations. The major changes in the microbial populations occurred during the first week of filter operation, and these populations then remained to the end of the study. Spatial and temporal nonlinear mapping of the DGGE bands provided a useful visual representation of the similarities between SSF samples. According to the DGGE profile, less than 2% of the dominating bands present in the SSF column were represented in the culturable population. Sequence analysis of DGGE bands from all depths of the SSF column indicated that a range of bacteria were present, with 16S rRNA gene sequences similar to groups such as Bacillus megaterium, Cytophaga, Desulfovibrio, Legionella, Rhodococcus rhodochrous, Sphingomonas, and an uncharacterized environmental clone. This study describes the characterization of the performance, and microbial composition, of SSFs used for the treatment of water for use in the horticultural industry. Utilization of naturally suppressive population of microorganisms either directly or by manipulation of the environment in an SSF may provide a more reproducible control method for the future.

scholarly journals Census of the Viral Metagenome within an Activated Sludge Microbial Assemblage

2010 ◽  
Vol 76 (8) ◽  
pp. 2673-2677 ◽  
Author(s):  
Larissa C. Parsley ◽  
Erin J. Consuegra ◽  
Stephen J. Thomas ◽  
Jaysheel Bhavsar ◽  
Andrew M. Land ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
16S Rrna ◽  
Activated Sludge ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Bacterial Isolates ◽  
Microbial Assemblage ◽  
Culture Independent ◽  
Culture Dependent

ABSTRACT The viral metagenome within an activated sludge microbial assemblage was sampled using culture-dependent and culture-independent methods and compared to the diversity of activated sludge bacterial taxa. A total of 70 unique cultured bacterial isolates, 24 cultured bacteriophages, 829 bacterial metagenomic clones of 16S rRNA genes, and 1,161 viral metagenomic clones were subjected to a phylogenetic analysis.

scholarly journals Effects of Heavy Fuel Oil on the Bacterial Community Structure of a Pristine Microbial Mat

2007 ◽  
Vol 73 (19) ◽  
pp. 6089-6097 ◽  
Author(s):  
Sylvain Bordenave ◽  
María Soledad Goñi-Urriza ◽  
Pierre Caumette ◽  
Robert Duran
Keyword(s):  
Community Structure ◽  
Bacterial Community ◽  
16S Rrna ◽  
Oil Pollution ◽  
Microbial Mat ◽  
Fuel Oil ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Heavy Fuel Oil

ABSTRACT The effects of petroleum contamination on the bacterial community of a pristine microbial mat from Salins-de-Giraud (Camargue, France) have been investigated. Mats were maintained as microcosms and contaminated with no. 2 fuel oil from the wreck of the Erika. The evolution of the complex bacterial community was monitored by combining analyses based on 16S rRNA genes and their transcripts. 16S rRNA gene-based terminal restriction fragment length polymorphism (T-RFLP) analyses clearly showed the effects of the heavy fuel oil after 60 days of incubation. At the end of the experiment, the initial community structure was recovered, illustrating the resilience of this microbial ecosystem. In addition, the responses of the metabolically active bacterial community were evaluated by T-RFLP and clone library analyses based on 16S rRNA. Immediately after the heavy fuel oil was added to the microcosms, the structure of the active bacterial community was modified, indicating a rapid microbial mat response. Members of the Gammaproteobacteria were initially dominant in the contaminated microcosms. Pseudomonas and Acinetobacter were the main genera representative of this class. After 90 days of incubation, the Gammaproteobacteria were superseded by “Bacilli” and Alphaproteobacteria. This study shows the major changes that occur in the microbial mat community at different time periods following contamination. At the conclusion of the experiment, the RNA approach also demonstrated the resilience of the microbial mat community in resisting environmental stress resulting from oil pollution.

scholarly journals Defining Metaniches in the Oral Cavity According to Their Microbial Composition and Cytokine Profile

2020 ◽  
Vol 21 (21) ◽  
pp. 8218
Author(s):  
Corinna L. Seidel ◽  
Roman G. Gerlach ◽  
Patrick Wiedemann ◽  
Matthias Weider ◽  
Gabriele Rodrian ◽  
...  
Keyword(s):  
Oral Cavity ◽  
Gingival Crevicular Fluid ◽  
Cytokine Profile ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Oral Microbiota ◽  
Microbial Composition ◽  
Periodontal Health ◽  
Culture Independent ◽  
Crevicular Fluid

The human oral microbiota consists of over 700 widespread taxa colonizing the oral cavity in several anatomically diverse oral niches. Lately, sequencing of the 16S rRNA genes has become an acknowledged, culture-independent method to characterize the oral microbiota. However, only a small amount of data are available concerning microbial differences between oral niches in periodontal health and disease. In the context of periodontitis, the cytokine expression in the gingival crevicular fluid has been studied in detail, whereas little is known about the cytokine profile in hard and soft tissue biofilms. In order to characterize oral niches in periodontal health, the oral microbiota and cytokine pattern were analyzed at seven different sites (plaque (P), gingival crevicular fluid (GCF), saliva (S), tongue (T), hard palate (HP), cheek (C) and sublingual area (U)) of 20 young adults using next-generation sequencing and multiplex immunoassays. Site-specific microbial compositions were detected, which clustered into three distinct metaniches (“P-GCF”, “S-T-HP” and “C-U”) and were associated with niche-/metaniche-specific cytokine profiles. Our findings allow the definition of distinct metaniches according to their microbial composition, partly reflected by their cytokine profile, and provide new insights into microenvironmental similarities between anatomical diverse oral niches.

scholarly journals Bacterial community structure in High-Arctic snow and freshwater as revealed by pyrosequencing of 16S rRNA genes and cultivation

2013 ◽  
Vol 32 (1) ◽  
pp. 17390 ◽  
Author(s):  
Annette K. Møller ◽  
Ditte A. Søborg ◽  
Waleed Abu Al-Soud ◽  
Søren J. Sørensen ◽  
Niels Kroer
Keyword(s):  
Community Structure ◽  
Bacterial Community ◽  
16S Rrna ◽  
Bacterial Community Structure ◽  
High Arctic ◽  
16S Rrna Genes ◽  
Rrna Genes

Abdominal setae and midgut bacteria of the mudshrimp Pestarella tyrrhena

2009 ◽  
Vol 4 (4) ◽  
pp. 558-566 ◽  
Author(s):  
Alexandra Demiri ◽  
Alexandra Meziti ◽  
Sokratis Papaspyrou ◽  
Maria Thessalou-Legaki ◽  
Konstantinos Kormas
Keyword(s):  
Bacterial Community ◽  
16S Rrna ◽  
Water Column ◽  
Redox Reactions ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Symbiotic Bacteria ◽  
Microbial Process

AbstractWe investigated the diversity of the bacterial 16S rRNA genes occurring on the abdominal setal tufts and in the emptied midgut of the marine mudshrimp Pestarella tyrrhena (Decapoda: Thalassinidea). There were no dominant phylotypes on the setal tufts. The majority of the phylotypes belonged to the phylum Bacteroidetes, frequently occurring in the water column. The rest of the phylotypes were related to anoxygenic photosynthetic α-Proteobacteria and to Actinobacteria. This bacterial profile seems more of a marine assemblage rather than a specific one suggesting that no specific microbial process can be inferred on the setal tufts. In the emptied midgut, 64 clones were attributed to 16 unique phylotypes with the majority (40.6%) belonging to the γ-Proteobacteria, specifically to the genus Vibrio, a marine group with known symbionts of decapods. The next most abundant group was the ɛ-Proteobacteria (28.1%), with members as likely symbionts related to the processes involving redox reactions occurring in the midgut. In addition, phylotypes related to the Spirochaetes (10.9%) were also present, with relatives capable of symbiosis conducting a nitrite associated metabolism. Entomoplasmatales, Bacteroidetes and Actinobacteria related phylotypes were also found. These results indicate a specific bacterial community dominated by putative symbiotic Bacteria within the P. tyrrhena’s midgut.

scholarly journals Increase in Terminal Restriction Fragments of Bacteroidetes-Derived 16S rRNA Genes after Administration of Short-Chain Fructooligosaccharides

2006 ◽  
Vol 72 (9) ◽  
pp. 6271-6276 ◽  
Author(s):  
Yusuke Nakanishi ◽  
Koichiro Murashima ◽  
Hiroki Ohara ◽  
Takahisa Suzuki ◽  
Hidenori Hayashi ◽  
...  
Keyword(s):  
16S Rrna ◽  
Intestinal Microbiota ◽  
Fragment Length Polymorphism ◽  
Rflp Analysis ◽  
Intestinal Bacteria ◽  
Short Chain ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Restriction Fragments ◽  
Culture Independent

ABSTRACT It is well known that short chain fructooligosaccharides (scFOS) modify intestinal microbiota in animals as well as in humans. Since most murine intestinal bacteria are still uncultured, it is difficult for a culturing method to detect changes in intestinal microbiota after scFOS administration in a mouse model. In this study, we sought markers of positive change in murine intestinal microbiota after scFOS administration using terminal restriction fragment length polymorphism (T-RFLP) analysis, which is a culture-independent method. The T-RFLP profiles showed that six terminal restriction fragments (T-RFs) were significantly increased after scFOS administration. Phylogenetic analysis of the 16S rRNA partial gene sequences of murine fecal bacteria suggested that four of six T-RFs that increased after scFOS administration were derived from the 16S rRNA genes of the class Bacteroidetes. Preliminary quantification of Bacteroidetes by real-time PCR suggests that the 16S rRNA genes derived from Bacteroidetes were increased by scFOS administration. Therefore, the T-RFs derived from Bacteroidetes are good markers of change of murine intestinal microbiota after scFOS administration.

Sign in / Sign up

Export Citation Format

Share Document