Home > Research > Publications & Outputs > A comparison of the growth and starvation respo...
View graph of relations

A comparison of the growth and starvation responses of Acanthamoeba castellanii and Hartmannella vermiformis in the presence of suspended and attached Escherichia coli K12

Research output: Contribution to journalJournal article

Published

Standard

A comparison of the growth and starvation responses of Acanthamoeba castellanii and Hartmannella vermiformis in the presence of suspended and attached Escherichia coli K12. / Pickup, Zoë L; Pickup, Roger; Parry, Jacqueline D.

In: FEMS Microbiology Ecology, Vol. 59, No. 3, 2007, p. 556-563.

Research output: Contribution to journalJournal article

Harvard

APA

Vancouver

Author

Bibtex

@article{c97694e0b04f4a5b96311866bc0964fb,
title = "A comparison of the growth and starvation responses of Acanthamoeba castellanii and Hartmannella vermiformis in the presence of suspended and attached Escherichia coli K12",
abstract = "The growth and starvation responses of Acanthamoeba castellanii and Hartmannella vermiformis were investigated in the presence and absence of Escherichia coli on an agar surface or within shaken suspensions. The amoebae perceived all the suspended systems to be unfavourable for growth, despite being challenged with high levels of prey, and as a consequence they exhibited a starvation response. However, the response differed between species, with A. castellanii producing characteristic cysts and H. vermiformis producing round bodies. These amoebic forms were reactivated into feeding trophozoites in the presence of bacterial aggregates, which formed in the suspended systems after 68 h of incubation. In contrast, both species of amoebae grew well in the presence of attached E. coli at a concentration of 1 x 10(6) cells cm(-2) of agar and yielded specific growth rates of c. 0.04 h(-1). Starvation responses were induced at the end of the growth phase, and these were equivalent to those recorded in the suspended systems. We conclude that, when suspended, amoebae in the 'floating form' cannot feed effectively on suspended prey, and hence the starvation response is initiated. Thus the majority of amoebic feeding is via trophozoite grazing of attached bacterial prey.",
keywords = "amoeba, cyst, yield, growth ratE, ingestion rate, biofilm",
author = "Pickup, {Zo{\"e} L} and Roger Pickup and Parry, {Jacqueline D}",
year = "2007",
doi = "10.1111/j.1574-6941.2006.00224.x",
language = "English",
volume = "59",
pages = "556--563",
journal = "FEMS Microbiology Ecology",
issn = "0168-6496",
publisher = "Wiley-Blackwell",
number = "3",

}

RIS

TY - JOUR

T1 - A comparison of the growth and starvation responses of Acanthamoeba castellanii and Hartmannella vermiformis in the presence of suspended and attached Escherichia coli K12

AU - Pickup, Zoë L

AU - Pickup, Roger

AU - Parry, Jacqueline D

PY - 2007

Y1 - 2007

N2 - The growth and starvation responses of Acanthamoeba castellanii and Hartmannella vermiformis were investigated in the presence and absence of Escherichia coli on an agar surface or within shaken suspensions. The amoebae perceived all the suspended systems to be unfavourable for growth, despite being challenged with high levels of prey, and as a consequence they exhibited a starvation response. However, the response differed between species, with A. castellanii producing characteristic cysts and H. vermiformis producing round bodies. These amoebic forms were reactivated into feeding trophozoites in the presence of bacterial aggregates, which formed in the suspended systems after 68 h of incubation. In contrast, both species of amoebae grew well in the presence of attached E. coli at a concentration of 1 x 10(6) cells cm(-2) of agar and yielded specific growth rates of c. 0.04 h(-1). Starvation responses were induced at the end of the growth phase, and these were equivalent to those recorded in the suspended systems. We conclude that, when suspended, amoebae in the 'floating form' cannot feed effectively on suspended prey, and hence the starvation response is initiated. Thus the majority of amoebic feeding is via trophozoite grazing of attached bacterial prey.

AB - The growth and starvation responses of Acanthamoeba castellanii and Hartmannella vermiformis were investigated in the presence and absence of Escherichia coli on an agar surface or within shaken suspensions. The amoebae perceived all the suspended systems to be unfavourable for growth, despite being challenged with high levels of prey, and as a consequence they exhibited a starvation response. However, the response differed between species, with A. castellanii producing characteristic cysts and H. vermiformis producing round bodies. These amoebic forms were reactivated into feeding trophozoites in the presence of bacterial aggregates, which formed in the suspended systems after 68 h of incubation. In contrast, both species of amoebae grew well in the presence of attached E. coli at a concentration of 1 x 10(6) cells cm(-2) of agar and yielded specific growth rates of c. 0.04 h(-1). Starvation responses were induced at the end of the growth phase, and these were equivalent to those recorded in the suspended systems. We conclude that, when suspended, amoebae in the 'floating form' cannot feed effectively on suspended prey, and hence the starvation response is initiated. Thus the majority of amoebic feeding is via trophozoite grazing of attached bacterial prey.

KW - amoeba

KW - cyst

KW - yield

KW - growth ratE

KW - ingestion rate

KW - biofilm

U2 - 10.1111/j.1574-6941.2006.00224.x

DO - 10.1111/j.1574-6941.2006.00224.x

M3 - Journal article

VL - 59

SP - 556

EP - 563

JO - FEMS Microbiology Ecology

JF - FEMS Microbiology Ecology

SN - 0168-6496

IS - 3

ER -