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Kenneth L Gage - One of the best experts on this subject based on the ideXlab platform.
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acquisition of bartonella elizabethae by experimentally exposed Oriental Rat Fleas xenopsylla cheopis siphonaptera pulicidae and excretion of bartonella dna in Flea feces
Journal of Medical Entomology, 2018Co-Authors: Clifton D Mckee, Lynn M Osikowicz, Teresa R Schwedhelm, Sarah E Maes, Russell E Enscore, Kenneth L Gage, Michael KosoyAbstract:: Few studies have been able to provide experimental evidence of the ability of Fleas to maintain rodent-associated Bartonella infections and excrete these bacteria. These data are important for understanding the transmission cycles and prevalence of these bacteria in hosts and vectors. We used an artificial feeding approach to expose groups of the Oriental Rat Flea (Xenopsylla cheopis Rothschild; Siphonaptera, Pulicidae) to Rat blood inoculated with varying concentRations of Bartonella elizabethae Daly (Bartonellaceae: Rhizobiales). Flea populations were maintained by membrane feeding on pathogen-free bloodmeals for up to 13 d post infection. Individual Fleas and pools of Flea feces were tested for the presence of Bartonella DNA using molecular methods (quantitative and conventional polymerase chain reaction [PCR]). The threshold number of Bartonellae required in the infectious bloodmeal for Fleas to be detected as positive was 106 colony-forming units per milliliter (CFU/ml). Individual Fleas were capable of harboring infections for at least 13 d post infection and continuously excreted Bartonella DNA in their feces over the same period. This experiment demonstRated that X. cheopis are capable of acquiring and excreting B. elizabethae over several days. These results will guide future work to model and understand the role of X. cheopis in the natural transmission cycle of rodent-borne Bartonella species. Future experiments using this artificial feeding approach will be useful for examining the horizontal transmission of B. elizabethae or other rodent-associated Bartonella species to naive hosts and for determining the viability of excreted bacteria.
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Evaluation of a Yersinia pestis mutant impaired in a thermoregulated type VI-like secretion system in Flea, macrophage and murine models.
Microbial pathogenesis, 2009Co-Authors: Jennilee B. Robinson, Kenneth L Gage, Scott W Bearden, John A Montenieri, Maxim V. Telepnev, Irina V. Zudina, Donald H. Bouyer, Stacy L. Agar, Sheri M. Foltz, Sadhana ChauhanAbstract:Type VI secretion systems (T6SSs) have been identified recently in several Gram-negative organisms and have been shown to be associated with virulence in some bacterial pathogens. A T6SS of Yersinia pestis CO92 (locus YPO0499-YPO0516) was deleted followed by investigation of the phenotype of this mutation. We observed that this T6SS locus of Y. pestis was preferentially expressed at 26 degrees C in comparison to 37 degrees C suggesting a possible role in the Flea cycle. However, we found that the deletion of T6SS locus YPO0499-YPO0516 in Y. pestis CO92 had no effect on the ability of this strain to infect the Oriental Rat Flea, Xenopsylla cheopis. Nevertheless, this mutant displayed increased intracellular numbers in macrophage-like J774.A1 cells after 20 h post-infection for bacterial cells pre-grown at 26 degrees C indicating that expression of this T6SS locus limited intracellular replication in macrophages. In addition, deletion of the YPO0499-YPO0516 locus reduced the uptake by macrophages of the Y. pestis mutant pre-grown at 37 degrees C, suggesting that this T6SS locus has phagocytosis-promoting activity. Further study of the virulence of the T6SS mutant in murine bubonic and inhalation plague models revealed no attenuation in comparison with the parental CO92 strain.
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Studies of Vector Competency and Efficiency of North American Fleas for Yersinia pestis: State of the Field and Future Research Needs
Journal of medical entomology, 2009Co-Authors: Rebecca J Eisen, Lars Eisen, Kenneth L GageAbstract:The etiological agent of plague, Yersinia pestis, is most commonly transmitted by the bite of infectious Fleas. To date, at least 28 Flea species occurring in North America have been experimentally confirmed as vectors of Y. pestis. Transmission efficiency differs among species and also between different studies of a single species. These differences may, however, in large part reflect nonstandardized experimental conditions used during the first half of the 20th century when such studies were conducted in response to the rapid spread of Y. pestis across the western United States after its introduction at the beginning of this century. The majority of these early transmission studies focused on the blocked Flea mechanism of transmission, which typically does not occur until > 2-3 wk after the Flea becomes infected. Recent studies have challenged the paradigm that Y. pestis is usually spread by blocked Fleas by demonstRating that numerous Flea species, including the Oriental Rat Flea Xenopsylla cheopis, which was the focus of the early classical studies on blocked Flea transmission, are capable of"early-phase" transmission during the first few days after becoming infected and before a complete blockage can form. The aims of this review are to 1) summarize Y. pestis vector competency and efficiency studies for Fleas occurring in North America, 2) discuss the implications of the results of these studies for our understanding of the dynamics of plague epizootics, 3) demonstRate why older transmission studies need to be repeated using a standardized experimental system, and 4) outline future directions for studies of Fleas as vectors of Y. pestis.
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early phase transmission of yersinia pestis by unblocked xenopsylla cheopis siphonaptera pulicidae is as efficient as transmission by blocked Fleas
Journal of Medical Entomology, 2007Co-Authors: Rebecca J Eisen, Aryn P Wilder, Scott W Bearden, John A Montenieri, Kenneth L GageAbstract:Abstract For almost a century, the Oriental Rat Flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae), was thought to be the most efficient vector of the plague bacterium Yersinia pestis (Yersin). Approximately 2 wk after consuming an infectious bloodmeal, a blockage often forms in the Flea’s proventriculus, which forces the Flea to increase its biting frequency and consequently increases the likelihood of transmission. However, if Fleas remain blocked and continue to feed, they usually die within 5 d of blocking, resulting in a short infectious window. Despite observations of X. cheopis transmitting Y. pestis shortly after pathogen acquisition, early-phase transmission (e.g., transmission 1–4 d postinfection [p.i.]) by unblocked Fleas was viewed as anomalous and thought to occur only by mass action. We used an artificial feeding system to infect colony-reared X. cheopis with a fully virulent strain of Y. pestis, and we evaluated transmission efficiency 1–4 d p.i. We demonstRate 1) that a single...
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Early-Phase Transmission of Yersinia pestis by Unblocked Xenopsylla cheopis (Siphonaptera: Pulicidae) Is as Efficient as Transmission by Blocked Fleas
Journal of medical entomology, 2007Co-Authors: Rebecca J Eisen, Aryn P Wilder, Scott W Bearden, John A Montenieri, Kenneth L GageAbstract:For almost a century, the Oriental Rat Flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae), was thought to be the most efficient vector of the plague bacterium Yersinia pestis (Yersin). Approximately 2 wk after consuming an infectious bloodmeal, a blockage often forms in the Flea's proventriculus, which forces the Flea to increase its biting frequency and consequently increases the likelihood of transmission. However, if Fleas remain blocked and continue to feed, they usually die within 5 d of blocking, resulting in a short infectious window. Despite observations of X. cheopis transmitting Y. pestis shortly after pathogen acquisition, early-phase transmission (e.g., transmission 1-4 d postinfection [ p.i.]) by unblocked Fleas was viewed as anomalous and thought to occur only by mass action. We used an artificial feeding system to infect colony-reared X. cheopis with a fully virulent strain of Y. pestis, and we evaluated transmission efficiency 1- 4 d p.i. We demonstRate 1) that a single infected and unblocked X. cheopis can infect a susceptible host as early as 1 d p.i., 2) the number of Fleas per host required for unblocked Fleas to drive a plague epizootic by early-phase transmission is within the Flea infestation range observed in nature, and 3) early-phase transmission by unblocked Fleas in the current study was at least as efficient as transmission by blocked Fleas in a previously published study using the same colony of Fleas and same bacterial strain. Furthermore, transmission efficiency seemed to remain constant until block formation, resulting in an infectious period considerably longer than previously thought.
Rebecca J Eisen - One of the best experts on this subject based on the ideXlab platform.
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Studies of Vector Competency and Efficiency of North American Fleas for Yersinia pestis: State of the Field and Future Research Needs
Journal of medical entomology, 2009Co-Authors: Rebecca J Eisen, Lars Eisen, Kenneth L GageAbstract:The etiological agent of plague, Yersinia pestis, is most commonly transmitted by the bite of infectious Fleas. To date, at least 28 Flea species occurring in North America have been experimentally confirmed as vectors of Y. pestis. Transmission efficiency differs among species and also between different studies of a single species. These differences may, however, in large part reflect nonstandardized experimental conditions used during the first half of the 20th century when such studies were conducted in response to the rapid spread of Y. pestis across the western United States after its introduction at the beginning of this century. The majority of these early transmission studies focused on the blocked Flea mechanism of transmission, which typically does not occur until > 2-3 wk after the Flea becomes infected. Recent studies have challenged the paradigm that Y. pestis is usually spread by blocked Fleas by demonstRating that numerous Flea species, including the Oriental Rat Flea Xenopsylla cheopis, which was the focus of the early classical studies on blocked Flea transmission, are capable of"early-phase" transmission during the first few days after becoming infected and before a complete blockage can form. The aims of this review are to 1) summarize Y. pestis vector competency and efficiency studies for Fleas occurring in North America, 2) discuss the implications of the results of these studies for our understanding of the dynamics of plague epizootics, 3) demonstRate why older transmission studies need to be repeated using a standardized experimental system, and 4) outline future directions for studies of Fleas as vectors of Y. pestis.
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early phase transmission of yersinia pestis by cat Fleas ctenocephalides felis and their potential role as vectors in a plague endemic region of uganda
American Journal of Tropical Medicine and Hygiene, 2008Co-Authors: Rebecca J Eisen, Russell E Enscore, Aryn P Wilder, Jeff N Borchert, Jennifer L Holmes, Gerald Amatre, Kristen Van Wyk, Nackson Babi, Linda A Atiku, Sara M VetterAbstract:In recent decades, the majority of human plague cases (caused by Yersinia pestis) have been reported from Africa. In northwest Uganda, which has had recent plague outbreaks, cat Fleas (Ctenocephalides felis) have been reported as the most common Fleas in the home environment, which is suspected to be a major exposure site for human plague in this country. In the past, C. felis has been viewed as only a nuisance-biting insect because limited laboRatory studies suggested it is incapable of transmitting Y. pestis or is an inefficient vector. Our laboRatory study shows that C. felis is a competent vector of plague bacteria, but that efficiency is low compared with another Flea species collected in the same area: the Oriental Rat Flea, Xenopsylla cheopis. On the other hand, despite its low vector efficiency, C. felis is the most common Flea in human habitations in a plague-endemic region of Uganda (Arua and Nebbi Districts), and occasionally infests potential rodent reservoirs of Y. pestis such as the roof Rat (Rattus Rattus) or the Nile Rat (Arvicanthis niloticus). Plague control programs in this region should remain focused on reducing Rat Flea populations, although our findings imply that cat Fleas should not be ignored by these programs as they could play a significant role as secondary vectors.
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early phase transmission of yersinia pestis by unblocked xenopsylla cheopis siphonaptera pulicidae is as efficient as transmission by blocked Fleas
Journal of Medical Entomology, 2007Co-Authors: Rebecca J Eisen, Aryn P Wilder, Scott W Bearden, John A Montenieri, Kenneth L GageAbstract:Abstract For almost a century, the Oriental Rat Flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae), was thought to be the most efficient vector of the plague bacterium Yersinia pestis (Yersin). Approximately 2 wk after consuming an infectious bloodmeal, a blockage often forms in the Flea’s proventriculus, which forces the Flea to increase its biting frequency and consequently increases the likelihood of transmission. However, if Fleas remain blocked and continue to feed, they usually die within 5 d of blocking, resulting in a short infectious window. Despite observations of X. cheopis transmitting Y. pestis shortly after pathogen acquisition, early-phase transmission (e.g., transmission 1–4 d postinfection [p.i.]) by unblocked Fleas was viewed as anomalous and thought to occur only by mass action. We used an artificial feeding system to infect colony-reared X. cheopis with a fully virulent strain of Y. pestis, and we evaluated transmission efficiency 1–4 d p.i. We demonstRate 1) that a single...
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Early-Phase Transmission of Yersinia pestis by Unblocked Xenopsylla cheopis (Siphonaptera: Pulicidae) Is as Efficient as Transmission by Blocked Fleas
Journal of medical entomology, 2007Co-Authors: Rebecca J Eisen, Aryn P Wilder, Scott W Bearden, John A Montenieri, Kenneth L GageAbstract:For almost a century, the Oriental Rat Flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae), was thought to be the most efficient vector of the plague bacterium Yersinia pestis (Yersin). Approximately 2 wk after consuming an infectious bloodmeal, a blockage often forms in the Flea's proventriculus, which forces the Flea to increase its biting frequency and consequently increases the likelihood of transmission. However, if Fleas remain blocked and continue to feed, they usually die within 5 d of blocking, resulting in a short infectious window. Despite observations of X. cheopis transmitting Y. pestis shortly after pathogen acquisition, early-phase transmission (e.g., transmission 1-4 d postinfection [ p.i.]) by unblocked Fleas was viewed as anomalous and thought to occur only by mass action. We used an artificial feeding system to infect colony-reared X. cheopis with a fully virulent strain of Y. pestis, and we evaluated transmission efficiency 1- 4 d p.i. We demonstRate 1) that a single infected and unblocked X. cheopis can infect a susceptible host as early as 1 d p.i., 2) the number of Fleas per host required for unblocked Fleas to drive a plague epizootic by early-phase transmission is within the Flea infestation range observed in nature, and 3) early-phase transmission by unblocked Fleas in the current study was at least as efficient as transmission by blocked Fleas in a previously published study using the same colony of Fleas and same bacterial strain. Furthermore, transmission efficiency seemed to remain constant until block formation, resulting in an infectious period considerably longer than previously thought.
Jose M C Ribeiro - One of the best experts on this subject based on the ideXlab platform.
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an insight into the sialome of the Oriental Rat Flea xenopsylla cheopis rots
BMC Genomics, 2007Co-Authors: John F Andersen, Joseph B Hinnebusch, David A Lucas, Thomas P Conrads, Timothy D Veenstra, Van My Pham, Jose M C RibeiroAbstract:The salivary glands of hematophagous animals contain a complex cocktail that interferes with the host hemostasis and inflammation pathways, thus increasing feeding success. Fleas represent a relatively recent group of insects that evolved hematophagy independently of other insect orders. Analysis of the salivary transcriptome of the Flea Xenopsylla cheopis, the vector of human plague, indicates that gene duplication events have led to a large expansion of a family of acidic phosphatases that are probably inactive, and to the expansion of the FS family of peptides that are unique to Fleas. Several other unique polypeptides were also uncovered. Additionally, an apyrase-coding transcript of the CD39 family appears as the candidate for the salivary nucleotide hydrolysing activity in X.cheopis, the first time this family of proteins is found in any arthropod salivary transcriptome. Analysis of the salivary transcriptome of the Flea X. cheopis revealed the unique pathways taken in the evolution of the salivary cocktail of Fleas. Gene duplication events appear as an important driving force in the creation of salivary cocktails of blood feeding arthropods, as was observed with ticks and mosquitoes. Only five other Flea salivary sequences exist at this time at NCBI, all from the cat Flea C. felis. This work accordingly represents the only relatively extensive sialome description of any Flea species. Sialotranscriptomes of additional Flea genera will reveal the extent that these novel polypeptide families are common throughout the Siphonaptera.
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An insight into the sialome of the Oriental Rat Flea, Xenopsylla cheopis (Rots)
BMC Genomics, 2007Co-Authors: John F Andersen, David A Lucas, Thomas P Conrads, Timothy D Veenstra, Van My Pham, B Joseph Hinnebusch, Jose M C RibeiroAbstract:Background The salivary glands of hematophagous animals contain a complex cocktail that interferes with the host hemostasis and inflammation pathways, thus increasing feeding success. Fleas represent a relatively recent group of insects that evolved hematophagy independently of other insect orders. Results Analysis of the salivary transcriptome of the Flea Xenopsylla cheopis , the vector of human plague, indicates that gene duplication events have led to a large expansion of a family of acidic phosphatases that are probably inactive, and to the expansion of the FS family of peptides that are unique to Fleas. Several other unique polypeptides were also uncovered. Additionally, an apyrase-coding transcript of the CD39 family appears as the candidate for the salivary nucleotide hydrolysing activity in X.cheopis , the first time this family of proteins is found in any arthropod salivary transcriptome. Conclusion Analysis of the salivary transcriptome of the Flea X. cheopis revealed the unique pathways taken in the evolution of the salivary cocktail of Fleas. Gene duplication events appear as an important driving force in the creation of salivary cocktails of blood feeding arthropods, as was observed with ticks and mosquitoes. Only five other Flea salivary sequences exist at this time at NCBI, all from the cat Flea C. felis . This work accordingly represents the only relatively extensive sialome description of any Flea species. Sialotranscriptomes of additional Flea genera will reveal the extent that these novel polypeptide families are common throughout the Siphonaptera.
Aryn P Wilder - One of the best experts on this subject based on the ideXlab platform.
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early phase transmission of yersinia pestis by cat Fleas ctenocephalides felis and their potential role as vectors in a plague endemic region of uganda
American Journal of Tropical Medicine and Hygiene, 2008Co-Authors: Rebecca J Eisen, Russell E Enscore, Aryn P Wilder, Jeff N Borchert, Jennifer L Holmes, Gerald Amatre, Kristen Van Wyk, Nackson Babi, Linda A Atiku, Sara M VetterAbstract:In recent decades, the majority of human plague cases (caused by Yersinia pestis) have been reported from Africa. In northwest Uganda, which has had recent plague outbreaks, cat Fleas (Ctenocephalides felis) have been reported as the most common Fleas in the home environment, which is suspected to be a major exposure site for human plague in this country. In the past, C. felis has been viewed as only a nuisance-biting insect because limited laboRatory studies suggested it is incapable of transmitting Y. pestis or is an inefficient vector. Our laboRatory study shows that C. felis is a competent vector of plague bacteria, but that efficiency is low compared with another Flea species collected in the same area: the Oriental Rat Flea, Xenopsylla cheopis. On the other hand, despite its low vector efficiency, C. felis is the most common Flea in human habitations in a plague-endemic region of Uganda (Arua and Nebbi Districts), and occasionally infests potential rodent reservoirs of Y. pestis such as the roof Rat (Rattus Rattus) or the Nile Rat (Arvicanthis niloticus). Plague control programs in this region should remain focused on reducing Rat Flea populations, although our findings imply that cat Fleas should not be ignored by these programs as they could play a significant role as secondary vectors.
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early phase transmission of yersinia pestis by unblocked xenopsylla cheopis siphonaptera pulicidae is as efficient as transmission by blocked Fleas
Journal of Medical Entomology, 2007Co-Authors: Rebecca J Eisen, Aryn P Wilder, Scott W Bearden, John A Montenieri, Kenneth L GageAbstract:Abstract For almost a century, the Oriental Rat Flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae), was thought to be the most efficient vector of the plague bacterium Yersinia pestis (Yersin). Approximately 2 wk after consuming an infectious bloodmeal, a blockage often forms in the Flea’s proventriculus, which forces the Flea to increase its biting frequency and consequently increases the likelihood of transmission. However, if Fleas remain blocked and continue to feed, they usually die within 5 d of blocking, resulting in a short infectious window. Despite observations of X. cheopis transmitting Y. pestis shortly after pathogen acquisition, early-phase transmission (e.g., transmission 1–4 d postinfection [p.i.]) by unblocked Fleas was viewed as anomalous and thought to occur only by mass action. We used an artificial feeding system to infect colony-reared X. cheopis with a fully virulent strain of Y. pestis, and we evaluated transmission efficiency 1–4 d p.i. We demonstRate 1) that a single...
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Early-Phase Transmission of Yersinia pestis by Unblocked Xenopsylla cheopis (Siphonaptera: Pulicidae) Is as Efficient as Transmission by Blocked Fleas
Journal of medical entomology, 2007Co-Authors: Rebecca J Eisen, Aryn P Wilder, Scott W Bearden, John A Montenieri, Kenneth L GageAbstract:For almost a century, the Oriental Rat Flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae), was thought to be the most efficient vector of the plague bacterium Yersinia pestis (Yersin). Approximately 2 wk after consuming an infectious bloodmeal, a blockage often forms in the Flea's proventriculus, which forces the Flea to increase its biting frequency and consequently increases the likelihood of transmission. However, if Fleas remain blocked and continue to feed, they usually die within 5 d of blocking, resulting in a short infectious window. Despite observations of X. cheopis transmitting Y. pestis shortly after pathogen acquisition, early-phase transmission (e.g., transmission 1-4 d postinfection [ p.i.]) by unblocked Fleas was viewed as anomalous and thought to occur only by mass action. We used an artificial feeding system to infect colony-reared X. cheopis with a fully virulent strain of Y. pestis, and we evaluated transmission efficiency 1- 4 d p.i. We demonstRate 1) that a single infected and unblocked X. cheopis can infect a susceptible host as early as 1 d p.i., 2) the number of Fleas per host required for unblocked Fleas to drive a plague epizootic by early-phase transmission is within the Flea infestation range observed in nature, and 3) early-phase transmission by unblocked Fleas in the current study was at least as efficient as transmission by blocked Fleas in a previously published study using the same colony of Fleas and same bacterial strain. Furthermore, transmission efficiency seemed to remain constant until block formation, resulting in an infectious period considerably longer than previously thought.
John F Andersen - One of the best experts on this subject based on the ideXlab platform.
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an insight into the sialome of the Oriental Rat Flea xenopsylla cheopis rots
BMC Genomics, 2007Co-Authors: John F Andersen, Joseph B Hinnebusch, David A Lucas, Thomas P Conrads, Timothy D Veenstra, Van My Pham, Jose M C RibeiroAbstract:The salivary glands of hematophagous animals contain a complex cocktail that interferes with the host hemostasis and inflammation pathways, thus increasing feeding success. Fleas represent a relatively recent group of insects that evolved hematophagy independently of other insect orders. Analysis of the salivary transcriptome of the Flea Xenopsylla cheopis, the vector of human plague, indicates that gene duplication events have led to a large expansion of a family of acidic phosphatases that are probably inactive, and to the expansion of the FS family of peptides that are unique to Fleas. Several other unique polypeptides were also uncovered. Additionally, an apyrase-coding transcript of the CD39 family appears as the candidate for the salivary nucleotide hydrolysing activity in X.cheopis, the first time this family of proteins is found in any arthropod salivary transcriptome. Analysis of the salivary transcriptome of the Flea X. cheopis revealed the unique pathways taken in the evolution of the salivary cocktail of Fleas. Gene duplication events appear as an important driving force in the creation of salivary cocktails of blood feeding arthropods, as was observed with ticks and mosquitoes. Only five other Flea salivary sequences exist at this time at NCBI, all from the cat Flea C. felis. This work accordingly represents the only relatively extensive sialome description of any Flea species. Sialotranscriptomes of additional Flea genera will reveal the extent that these novel polypeptide families are common throughout the Siphonaptera.
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An insight into the sialome of the Oriental Rat Flea, Xenopsylla cheopis (Rots)
BMC Genomics, 2007Co-Authors: John F Andersen, David A Lucas, Thomas P Conrads, Timothy D Veenstra, Van My Pham, B Joseph Hinnebusch, Jose M C RibeiroAbstract:Background The salivary glands of hematophagous animals contain a complex cocktail that interferes with the host hemostasis and inflammation pathways, thus increasing feeding success. Fleas represent a relatively recent group of insects that evolved hematophagy independently of other insect orders. Results Analysis of the salivary transcriptome of the Flea Xenopsylla cheopis , the vector of human plague, indicates that gene duplication events have led to a large expansion of a family of acidic phosphatases that are probably inactive, and to the expansion of the FS family of peptides that are unique to Fleas. Several other unique polypeptides were also uncovered. Additionally, an apyrase-coding transcript of the CD39 family appears as the candidate for the salivary nucleotide hydrolysing activity in X.cheopis , the first time this family of proteins is found in any arthropod salivary transcriptome. Conclusion Analysis of the salivary transcriptome of the Flea X. cheopis revealed the unique pathways taken in the evolution of the salivary cocktail of Fleas. Gene duplication events appear as an important driving force in the creation of salivary cocktails of blood feeding arthropods, as was observed with ticks and mosquitoes. Only five other Flea salivary sequences exist at this time at NCBI, all from the cat Flea C. felis . This work accordingly represents the only relatively extensive sialome description of any Flea species. Sialotranscriptomes of additional Flea genera will reveal the extent that these novel polypeptide families are common throughout the Siphonaptera.