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Applied and Environmental Microbiology Dec 2005Electron microscopic analysis of contractile phage tail-like bacteriocins of three Pragia fontium strains and one Budvicia aquatica strain was performed. Fonticin and...
Electron microscopic analysis of contractile phage tail-like bacteriocins of three Pragia fontium strains and one Budvicia aquatica strain was performed. Fonticin and aquaticin are remarkably heat sensitive but trypsin resistant. Simultaneous production of contractile and flexible phage tail-like bacteriocins in the P. fontium 64613 strain is shown for the first time.
Topics: Bacteriocins; Bacteriophages; Enterobacteriaceae; Microscopy, Electron; Molecular Weight; Sensitivity and Specificity
PubMed: 16332902
DOI: 10.1128/AEM.71.12.8970-8973.2005 -
Microbiology and Immunology Jul 2008Bacterial 16S ribosomal RNA genes (rDNA) were detected in blood samples from two healthy individuals by PCR under conditions involving 30 cycles that did not produce any...
Bacterial 16S ribosomal RNA genes (rDNA) were detected in blood samples from two healthy individuals by PCR under conditions involving 30 cycles that did not produce any visible products from negative control saline. Even from control samples, PCR involving 35-40 cycles yielded visible bands. Major clones detected in the blood samples, but not in control, were the Aquabacterium subgroup, Stenotrophomonas subgroup, Budvicia subgroup, Serratia subgroup, Bacillus subgroup and Flavobacteria subgroup. No clone was located within the bacteroides-clostridium-lactobacillus cluster, which is indigenous to gastrointestinal flora.
Topics: Bacteremia; Bacteria; Blood; DNA, Bacterial; DNA, Ribosomal; Humans; Polymerase Chain Reaction; RNA, Ribosomal, 16S
PubMed: 18667036
DOI: 10.1111/j.1348-0421.2008.00048.x -
BMC Microbiology May 2014The red palm weevil (RPW) Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) is one of the major pests of palms. The larvae bore into the palm trunk and feed...
BACKGROUND
The red palm weevil (RPW) Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) is one of the major pests of palms. The larvae bore into the palm trunk and feed on the palm tender tissues and sap, leading the host tree to death. The gut microbiota of insects plays a remarkable role in the host life and understanding the relationship dynamics between insects and their microbiota may improve the biological control of insect pests. The purpose of this study was to analyse the diversity of the gut microbiota of field-caught RPW larvae sampled in Sicily (Italy).
RESULTS
The 16S rRNA gene-based Temporal Thermal Gradient Gel Electrophoresis (TTGE) of the gut microbiota of RPW field-trapped larvae revealed low bacterial diversity and stability of the community over seasons and among pools of larvae from different host trees. Pyrosequencing of the 16S rRNA gene V3 region confirmed low complexity and assigned 98% of the 75,564 reads to only three phyla: Proteobacteria (64.7%) Bacteroidetes (23.6%) and Firmicutes (9.6%) and three main families [Enterobacteriaceae (61.5%), Porphyromonadaceae (22.1%) and Streptococcaceae (8.9%)]. More than half of the reads could be classified at the genus level and eight bacterial genera were detected in the larval RPW gut at an abundance ≥1%: Dysgonomonas (21.8%), Lactococcus (8.9%), Salmonella (6.8%), Enterobacter (3.8%), Budvicia (2.8%), Entomoplasma (1.4%), Bacteroides (1.3%) and Comamonas (1%). High abundance of Enterobacteriaceae was also detected by culturing under aerobic conditions. Unexpectedly, acetic acid bacteria (AAB), that are known to establish symbiotic associations with insects relying on sugar-based diets, were not detected.
CONCLUSIONS
The RPW gut microbiota is composed mainly of facultative and obligate anaerobic bacteria with a fermentative metabolism. These bacteria are supposedly responsible for palm tissue fermentation in the tunnels where RPW larvae thrive and might have a key role in the insect nutrition, and other functions that need to be investigated.
Topics: Animals; Biota; Carbohydrates; Cluster Analysis; Cytosol; DNA, Bacterial; DNA, Ribosomal; Gastrointestinal Tract; Italy; Larva; Molecular Sequence Data; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Sicily; Weevils
PubMed: 24884866
DOI: 10.1186/1471-2180-14-136