scholarly journals Bacterial Metabolic Potential and Micro-Eukaryotes Enriched in Stony Coral Tissue Loss Disease Lesions

2022 ◽  
Vol 8 ◽  
Author(s):  
Stephanie M. Rosales ◽  
Lindsay K. Huebner ◽  
Abigail S. Clark ◽  
Ryan McMinds ◽  
Rob R. Ruzicka ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Energy Efficient ◽  
South Florida ◽  
Tissue Loss ◽  
Coral Tissue ◽  
Rrna Gene ◽  
Nucleotide Biosynthesis ◽  
Stony Coral ◽  
Eukaryotic Community

The epizootic disease outbreak known as stony coral tissue loss disease (SCTLD) is arguably the most devastating coral disease in recorded history. SCTLD emerged off the coast of South Florida in 2014 and has since moved into the Caribbean, resulting in coral mortality rates that have changed reef structure and function. Currently, the cause of SCTLD is unknown, but there is evidence from 16S rRNA gene sequencing and bacterial culture studies that the microbial community plays a role in the progression of SCTLD lesions. In this study, we applied shotgun metagenomics to characterize the potential function of bacteria, as well as the composition of the micro-eukaryotic community, associated with SCTLD lesions. We re-examined samples that were previously analyzed using 16S rRNA gene high-throughput sequencing from four coral species: Stephanocoenia intersepta, Diploria labyrinthiformis, Dichocoenia stokesii, and Meandrina meandrites. For each species, tissue from apparently healthy (AH) corals, and unaffected tissue (DU) and lesion tissue (DL) on diseased corals, were collected from sites within the epidemic zone of SCTLD in the Florida Keys. Within the micro-eukaryotic community, the taxa most prominently enriched in DL compared to AH and DU tissue were members of Ciliophora. We also found that DL samples were relatively more abundant in less energy-efficient pathways like the pentose phosphate pathways. While less energy-efficient processes were identified, there were also relatively higher abundances of nucleotide biosynthesis and peptidoglycan maturation pathways in diseased corals compared to AH, which suggests there was more bacteria growth in diseased colonies. In addition, we generated 16 metagenome-assembled genomes (MAGs) belonging to the orders Pseudomonadales, Beggiatoales, Rhodobacterales, Rhizobiales, Rs-D84, Flavobacteriales, and Campylobacterales, and all MAGs were enriched in DL samples compared to AH samples. Across all MAGs there were antibiotic resistance genes that may have implications for the treatment of SCTLD with antibiotics. We also identified genes and pathways linked to virulence, such as nucleotide biosynthesis, succinate dehydrogenase, ureases, nickel/iron transporters, Type-1 secretion system, and metalloproteases. Some of these enzymes/pathways have been previously targeted in the treatment of other bacterial diseases and they may be of interest to mitigate SCTLD lesion progression.

scholarly journals First Report of Bacterial Leaf Spot on Cichorium intybus Caused by Pseudomonas cichorii in Florida

Plant Disease ◽  
2013 ◽  
Vol 97 (6) ◽  
pp. 837-837 ◽  
Author(s):  
S. Zhang ◽  
Y. Fu
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Leaf Spot ◽  
South Florida ◽  
Cichorium Intybus ◽  
Rrna Gene ◽  
Fluorescent Pseudomonad ◽  
Bacterial Leaf Spot ◽  
Pseudomonas Cichorii ◽  
First Report

Italian dandelion (Cichorium intybus L.) is a leafy chicory plant grown as a fresh vegetable in salads. In August 2011, necrotic lesions were observed on leaves of about 20% of the Italian dandelion plants in an experimental field at the Tropical Research and Education Center (TREC) of the University of Florida in Homestead, FL. The lesions were dark brown with a yellow halo and most were irregular in shape. Some lesions formed along the leaf edge and developed into large lesions up to 20 to 30 mm long. Symptomatic leaf tissues were cut into small pieces (2 to 3 mm), sterilized in 10% Clorox (0.6% sodium hypochlorite) for 2 min following surface disinfection in 70% ethanol for 30 s, placed on nutrient agar (NA), and incubated at 28°C in the dark for 4 to 5 days. A bacterium was consistently isolated from the leaf lesions. Colonies of these bacteria were raised, opaque, and round with a slightly irregular, colorless margin while the center was light brown. The colonies were gram-negative with yellow fluorescence appearance on Pseudomonas F agar (Becton, Dickinson and Company, Sparks, MD). LOPAT tests were carried out to further identify the species of this fluorescent pseudomonad (2). The bacterium was levan negative, oxidase positive, potato rot negative, arginine dihydrolase negative, and tobacco hypersensitivity positive. Results from this test indicated that the bacterium belongs to LOPAT group III of fluorescent pseudomonads. Bacterial identity was further confirmed as Pseudomonas cichorii by amplifying the 16S rRNA gene with the universal bacterial primers 8F and 1492R (1) and sequence analysis (GenBank Accession No. KC311733). The partial 1,361-bp 16S rRNA gene sequences had 100% identity with P. cichorii (JF951725.1), which was isolated from infected soybean plants. Pathogenicity of the isolate was tested twice by spraying a suspension of the bacterium (107 CFU/ml) onto three 4-week-old plants until runoff. The control plants were sprayed with sterile distilled water. All plants were covered with plastic bags to maintain moisture for 48 h in an air-conditioned greenhouse (22 ± 1°C). Similar lesions were observed on the inoculated plant leaves 5 to 7 days after inoculation, whereas no lesions were developed on the control plants. Bacterial colonies with same morphology were recovered from the lesions, fulfilling Koch's postulates. P. cichorii is widespread worldwide with an important economic impact on celery, chrysanthemum, and lettuce. In South Florida, P. cichorii was reported as the causal agent of bacterial leaf spot on escarole (Cichorium endivia L.) (3). To our knowledge, this is the first report of bacterial leaf spot on Italian dandelion caused by P. cichorii in Florida. References: (1) J. P. Galkiewicz and C. A. Kellogg. Appl. Environ. Microbiol. 74:7828, 2008. (2) T. Goszczynska et al. Introduction to Practical Phytobacteriology. Isteg Scientific Publications, Irene, South Africa, 2000. (3) K. Pernezny and R. N. Raid. Plant Dis. 85:1208, 2001.

Differentiation Of Clarias Batrachus, C. Gariepinus And Heteropneustes Fossilis By Pcr-Sequencing Of Mitochondrial 16s Rrna Gene

2015 ◽  
Vol 41 (1) ◽  
pp. 51-58
Author(s):  
Mohammad Shamimul Alam ◽  
Hawa Jahan ◽  
Rowshan Ara Begum ◽  
Reza M Shahjahan
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Fish Larva ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Valuable Insight ◽  
Multiple Sequence ◽  
Pcr Rflp ◽  
Alternative Means

Heteropneustesfossilis, Clariasbatrachus and C. gariepinus are three major catfishes ofecological and economic importance. Identification of these fish species becomes aproblem when the usual external morphological features of the fish are lost or removed,such as in canned fish. Also, newly hatched fish larva is often difficult to identify. PCRsequencingprovides accurate alternative means of identification of individuals at specieslevel. So, 16S rRNA genes of three locally collected catfishes were sequenced after PCRamplification and compared with the same gene sequences available from othergeographical regions. Multiple sequence alignment of the 16S rRNA gene fragments ofthe catfish species has revealed polymorphic sites which can be used to differentiate thesethree species from one another and will provide valuable insight in choosing appropriaterestriction enzymes for PCR-RFLP based identification in future. Asiat. Soc. Bangladesh, Sci. 41(1): 51-58, June 2015

Marine mammals are natural hosts of Oceanivirga salmonicida, a bacterial pathogen of Atlantic salmon

2020 ◽  
Vol 139 ◽  
pp. 161-174
Author(s):  
R Palmer ◽  
GTA Fleming ◽  
S Glaeser ◽  
T Semmler ◽  
A Flamm ◽  
...  
Keyword(s):  
16S Rrna ◽  
Atlantic Salmon ◽  
16S Rrna Gene ◽  
Marine Mammals ◽  
Rrna Gene ◽  
Bacterial Disease ◽  
Common Dolphin ◽  
Stenella Coeruleoalba ◽  
Striped Dolphin ◽  
Natural Hosts

During 1992 and 1993, a bacterial disease occurred in a seawater Atlantic salmon Salmo salar farm, causing serious mortalities. The causative agent was subsequently named as Oceanivirga salmonicida, a member of the Leptotrichiaceae. Searches of 16S rRNA gene sequence databases have shown sequence similarities between O. salmonicida and uncultured bacterial clones from the digestive tracts of marine mammals. In the current study, oral samples were taken from stranded dolphins (common dolphin Delphinus delphis, striped dolphin Stenella coeruleoalba) and healthy harbour seals Phoca vitulina. A bacterium with growth characteristics consistent with O. salmonicida was isolated from a common dolphin. The isolate was confirmed as O. salmonicida, by comparisons to the type strain, using 16S rRNA gene, gyrB, groEL, and recA sequence analyses, average nucleotide identity analysis, and MALDI-TOF mass spectrometry. Metagenomic analysis indicated that the genus Oceanivirga represented a significant component of the oral bacterial microbiomes of the dolphins and seals. However, sequences consistent with O. salmonicida were only found in the dolphin samples. Analyses of marine mammal microbiome studies in the NCBI databases showed sequences consistent with O. salmonicida from the common dolphin, striped dolphin, bottlenose dolphin Tursiops truncatus, humpback whale Megaptera novaeangliae, and harbour seal. Sequences from marine environmental studies in the NCBI databases showed no sequences consistent with O. salmonicida. The findings suggest that several species of marine mammals are natural hosts of O. salmonicida.

Monoglobus pectinilyticus gen. nov., sp. nov., a pectinolytic bacterium isolated from human faeces.

2020 ◽  
Author(s):  
CC Kim ◽  
WJ Kelly ◽  
ML Patchett ◽  
GW Tannock ◽  
Z Jordens ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Sequence Similarity ◽  
Middle Lamella ◽  
Rrna Gene ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Citrus Peel ◽  
Human Faeces ◽  
The Family

© 2017 IUMS. A novel anaerobic pectinolytic bacterium (strain 14T) was isolated from human faeces. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 14T belonged to the family Ruminococcaceae, but was located separately from known clostridial clusters within the taxon. The closest cultured relative of strain 14T was Acetivibrio cellulolyticus (89.7% sequence similarity). Strain 14T shared ~99% sequence similarity with cloned 16S rRNA gene sequences from uncultured bacteria derived from the human gut. Cells were Gram-stain-positive, non-motile cocci approximately 0.6μm in diameter. Strain 14T fermented pectins from citrus peel, apple, and kiwifruit as well as carbohydrates that are constituents of pectins and hemicellulose, such as galacturonic acid, xylose, and arabinose. TEM images of strain 14T, cultured in association with plant tissues, suggested extracellular fibrolytic activity associated with the bacterial cells, forming zones of degradation in the pectin-rich regions of middle lamella. Phylogenetic and phenotypic analysis supported the differentiation of strain 14T as a novel genus in the family Ruminococcaceae. The name Monoglobus pectinilyticus gen. nov., sp. nov. is proposed; the type strain is 14T (JCM 31914T=DSM 104782T).

Screening and Molecular Characterization of Cellulase Producing Actinobacteria from Litchi Orchard

2019 ◽  
Vol 13 (1) ◽  
pp. 90-101
Author(s):  
Sanju Kumari ◽  
Utkarshini Sharma ◽  
Rohit Krishna ◽  
Kanak Sinha ◽  
Santosh Kumar
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Molecular Characterization ◽  
Biochemical Characterization ◽  
Evolutionary Relationship ◽  
Gene Sequencing ◽  
Cellulase Activity ◽  
16S Rrna Gene Sequencing ◽  
Rrna Gene ◽  
Rrna Gene Sequencing

Background: Cellulolysis is of considerable economic importance in laundry detergents, textile and pulp and paper industries and in fermentation of biomass into biofuels. Objective: The aim was to screen cellulase producing actinobacteria from the fruit orchard because of its requirement in several chemical reactions. Methods: Strains of actinobacteria were isolated on Sabouraud’s agar medium. Similarities in cultural and biochemical characterization by growing the strains on ISP medium and dissimilarities among them perpetuated to recognise nine groups of actinobacteria. Cellulase activity was measured by the diameter of clear zone around colonies on CMC agar and the amount of reducing sugar liberated from carboxymethyl cellulose in the supernatant of the CMC broth. Further, 16S rRNA gene sequencing and molecular characterization were placed before NCBI for obtaining recognition with accession numbers. Results: Prominent clear zones on spraying Congo Red were found around the cultures of strains of three groups SK703, SK706, SK708 on CMC agar plates. The enzyme assay for carboxymethylcellulase displayed extra cellulase activity in broth: 0.14, 0.82 and 0.66 µmol mL-1 min-1, respectively at optimum conditions of 35°C, pH 7.3 and 96 h of incubation. However, the specific cellulase activities per 1 mg of protein did not differ that way. It was 1.55, 1.71 and 1.83 μmol mL-1 min-1. The growing mycelia possessed short compact chains of 10-20 conidia on aerial branches. These morphological and biochemical characteristics, followed by their verification by Bergey’s Manual, categorically allowed the strains to be placed under actinobacteria. Further, 16S rRNA gene sequencing, molecular characterization and their evolutionary relationship through phylogenetics also confirmed the putative cellulase producing isolates of SK706 and SK708 subgroups to be the strains of Streptomyces. These strains on getting NCBI recognition were christened as Streptomyces glaucescens strain SK91L (KF527284) and Streptomyces rochei strain SK78L (KF515951), respectively. Conclusion: Conclusive evidence on the basis of different parameters established the presence of cellulase producing actinobacteria in the litchi orchard which can convert cellulose into fermentable sugar.

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