&lt;span style=" font-size

Abebe, Eyaulem; Abebe-Akele, Feseha; Morrison, Julie; Cooper, Vaughn S.; Thomas, W. Kelley

doi:10.4161/viru.2.2.15337

Cited by 37 publications

(24 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…marcescens (including the type strain), and two genomes of other Serratia species. Interestingly, the closest genome match (98.49% similarity, as shown by AAI identity scores listed in the S1 Dataset) of Ss1 is to Serratia sp SCBI [31,32], a pathogen of the lepidopteran Galleria mellonella (honey comb moth), which is a pest of honey bee colonies. The complete dendrogram that includes the phylogenetic relationships of all 42 Serratia genomes based on AAI analysis is also provided as an unrooted phylogenetic tree (S2 Fig), and their distance scale values are shown in S1 Dataset.…”

Section: Resultsmentioning

confidence: 99%

Sepsis and Hemocyte Loss in Honey Bees (Apis mellifera) Infected with Serratia marcescens Strain Sicaria

et al. 2016

View full text Add to dashboard Cite

Global loss of honey bee colonies is threatening the human food supply. Diverse pathogens reduce honey bee hardiness needed to sustain colonies, especially in winter. We isolated a free-living Gram negative bacillus from hemolymph of worker honey bees (Apis mellifera) found separated from winter clusters. In some hives, greater than 90% of the dying bees detached from the winter cluster were found to contain this bacterium in their hemolymph. Throughout the year, the same organism was rarely found in bees engaged in normal hive activities, but was detected in about half of Varroa destructor mites obtained from colonies that housed the septic bees. Flow cytometry of hemolymph from septic bees showed a significant reduction of plasmatocytes and other types of hemocytes. Interpretation of the16S rRNA sequence of the bacterium indicated that it belongs to the Serratia genus of Gram-negative Gammaproteobacteria, which has not previously been implicated as a pathogen of adult honey bees. Complete genome sequence analysis of the bacterium supported its classification as a novel strain of Serratia marcescens, which was designated as S. marcescens strain sicaria (Ss1). When compared with other strains of S. marcescens, Ss1 demonstrated several phenotypic and genetic differences, including 65 genes not previously found in other Serratia genomes. Some of the unique genes we identified in Ss1 were related to those from bacterial insect pathogens and commensals. Recovery of this organism extends a complex pathosphere of agents which may contribute to failure of honey bee colonies.

show abstract

Section: Resultsmentioning

confidence: 99%

Sepsis and Hemocyte Loss in Honey Bees (Apis mellifera) Infected with Serratia marcescens Strain Sicaria

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Differential gene expression was calculated by normalizing the data utilizing the trimmed mean of M-values normalization method and filtering out genes that had <10 counts per million (CPM) within the edgeR package (35). Statistical analysis was performed in RStudio (v 0.98.1102) (36) by the exact test with a negative binomial distribution for each set of conditions and testing for differential gene expression using edgeR (35). Differentially expressed genes were determined to be statistically significant based on an adjusted p < 0.05.…”

Section: Methodsmentioning

confidence: 99%

Elizabethkingia anophelisresponse to iron stress: physiologic, genomic, and transcriptomic analyses

Chen

Johnson

et al. 2019

Preprint

View full text Add to dashboard Cite

28Elizabethkingia anophelis bacteria encounter fluxes of iron in the midgut of mosquitoes, 29where they live as symbionts. They also establish bacteremia with severe clinical 30 manifestations in humans, and live in water service lines in hospitals. In this study, we 31 investigated the global gene expression responses of E. anophelis to iron fluxes in the midgut 32 of female Anopheles stephensi mosquitoes fed sucrose or blood, and in iron-poor or iron-rich 33 culture conditions. Of 3,686 transcripts revealed by RNAseq technology, 218 were upregulated 34 while 112 were down-regulated under iron-poor conditions. Most of these differentially 35 expressed genes (DEGs) were enriched in functional groups assigned within "biological 36 process," "cell component" and "molecular function" categories. E. anophelis possessed 4 37 iron/heme acquisition systems. Hemolysin gene expression was significantly repressed when 38 cells were grown under iron-rich or high temperature (37℃) conditions. Furthermore, 39 hemolysin gene expression was down-regulated after a blood meal, indicating that E. anophelis 40 cells responded to excess iron and its associated physiological stress by limiting iron loading. 41By contrast, genes encoding respiratory chain proteins were up-regulated under iron-rich 42 conditions, allowing these iron-containing proteins to chelate intracellular free iron. In vivo 43 studies showed that growth of E. anophelis cells increased 3-fold in blood-fed mosquitoes over 44 those in sucrose-fed ones. Deletion of aerobactin synthesis genes led to impaired cell growth 45 in both iron-rich and iron-poor media. Mutants showed more susceptibility to H 2 O 2 toxicity 46 and less biofilm formation than did wild-type cells. Mosquitoes with E. anophelis 47 experimentally colonized in their guts produced more eggs than did those treated with 48 erythromycin or left unmanipulated, as controls. Results reveal that E. anophelis bacteria 49 respond to varying iron concentration in the mosquito gut, harvest iron while fending off iron-50 associated stress, contribute to lysis of red blood cells, and positively influence mosquito host 51 fecundity. 52

show abstract

“…2009; Abebe et al. 2011). However, genome characterization of these two species revealed that their genome characteristics are similar to those non-host-restricted Serratia , with a chromosome that is >5 Mb in size, 55%–60% GC and containing >4500 CDSs (Taira et al.…”

Section: Recent Progress In Facultative Insect Symbiontsmentioning

confidence: 99%

Winding paths to simplicity: genome evolution in facultative insect symbionts

Huang

Kuo

2016

FEMS Microbiology Reviews

100

110

View full text Add to dashboard Cite

Symbiosis between organisms is an important driving force in evolution. Among the diverse relationships described, extensive progress has been made in insect–bacteria symbiosis, which improved our understanding of the genome evolution in host-associated bacteria. Particularly, investigations on several obligate mutualists have pushed the limits of what we know about the minimal genomes for sustaining cellular life. To bridge the gap between those obligate symbionts with extremely reduced genomes and their non-host-restricted ancestors, this review focuses on the recent progress in genome characterization of facultative insect symbionts. Notable cases representing various types and stages of host associations, including those from multiple genera in the family Enterobacteriaceae (class Gammaproteobacteria), Wolbachia (Alphaproteobacteria) and Spiroplasma (Mollicutes), are discussed. Although several general patterns of genome reduction associated with the adoption of symbiotic relationships could be identified, extensive variation was found among these facultative symbionts. These findings are incorporated into the established conceptual frameworks to develop a more detailed evolutionary model for the discussion of possible trajectories. In summary, transitions from facultative to obligate symbiosis do not appear to be a universal one-way street; switches between hosts and lifestyles (e.g. commensalism, parasitism or mutualism) occur frequently and could be facilitated by horizontal gene transfer.

show abstract

<span style=" font-size

Cited by 37 publications

References 21 publications

Sepsis and Hemocyte Loss in Honey Bees (Apis mellifera) Infected with Serratia marcescens Strain Sicaria

Sepsis and Hemocyte Loss in Honey Bees (Apis mellifera) Infected with Serratia marcescens Strain Sicaria

Elizabethkingia anophelisresponse to iron stress: physiologic, genomic, and transcriptomic analyses

Winding paths to simplicity: genome evolution in facultative insect symbionts

Contact Info

Product

Resources

About