PMID- 8720945
OWN - NLM
STAT- MEDLINE
DCOM- 19961010
LR  - 20190920
IS  - 1066-5234 (Print)
IS  - 1066-5234 (Linking)
VI  - 43
IP  - 2
DP  - 1996 Mar-Apr
TI  - Chemosensory responses of Acanthamoeba castellanii: visual analysis of random 
      movement and responses to chemical signals.
PG  - 150-8
AB  - A visual assay slide chamber was used in conjunction with time-lapse 
      videomicroscopy to analyze chemotactic behavior of axenically grown Acanthamoeba 
      castellanii. Data were collected and analyzed as vector scatter diagrams and cell 
      tracks. Amebas responded to a variety of bacterial products or potential 
      bacterial products by moving actively toward the attractant. Responses to the 
      chemotactic peptide formyl-methionyl-leucyl-phenylalanine (fMLP), 
      lipopolysaccharide, and lipid A were statistically significant (P < or = 0.03), 
      as was the response to fMLP benzylamide (P < or = 0.05). Significant responses to 
      cyclic AMP, lipoteichoic acid, and N-acetyl glucosamine were also found. 
      Chemotactic peptide antagonists, mannose, mannosylated bovine serum albumin, and 
      N-acetyl muramic acid all yielded nonsignificant responses (P > 0.05). There was 
      no single optimal concentration for response to any of the attractants tested, 
      and amebas responded equally over the range of concentrations tested. 
      Pretreatment of amebas with chemotactic peptides, bacterial products, and 
      bacteria reduced the directional response to attractants. Amebas that had been 
      grown in the presence of bacteria appeared more responsive to chemotactic 
      peptides. Treatment of amebas with trypsin reduced the response of cells to 
      chemotactic peptides, though sensitivity was restored within a couple of hours. 
      This suggests the ameba membrane may have receptors, sensitive to these bacterial 
      substances, which are different from the mannose receptors involved in binding 
      bacteria to the membrane during phagocytosis. The rate of movement was relatively 
      constant (ca. 0.40 microns/s), indicating that the locomotor response to these 
      signals is a taxis, or possibly a klinokinesis, but not an orthokinesis. Studies 
      of the population diffusion rate in the absence of signals indicate that the 
      basic population motility follows the pattern of a Levy walk, rather than the 
      more familiar Gaussian diffusion. This suggests that the usual mathematical 
      models of ameboid dispersion may need to be modified.
FAU - Schuster, F L
AU  - Schuster FL
AD  - Biology Department, Brooklyn College, New York 11210, USA.
FAU - Levandowsky, M
AU  - Levandowsky M
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PL  - United States
TA  - J Eukaryot Microbiol
JT  - The Journal of eukaryotic microbiology
JID - 9306405
RN  - 0 (Chemotactic Factors)
RN  - 0 (Lipopolysaccharides)
RN  - 59880-97-6 (N-Formylmethionine Leucyl-Phenylalanine)
SB  - IM
MH  - Acanthamoeba/drug effects/growth & development/*physiology
MH  - Animals
MH  - Chemotactic Factors/*pharmacology
MH  - *Chemotaxis
MH  - Escherichia coli/immunology
MH  - Klebsiella pneumoniae/immunology
MH  - Lipopolysaccharides/pharmacology
MH  - Microscopy, Video
MH  - N-Formylmethionine Leucyl-Phenylalanine/analogs & derivatives/pharmacology
MH  - Phagocytosis
MH  - Random Allocation
MH  - Salmonella enteritidis
MH  - Time Factors
EDAT- 1996/03/01 00:00
MHDA- 1996/03/01 00:01
CRDT- 1996/03/01 00:00
PHST- 1996/03/01 00:00 [pubmed]
PHST- 1996/03/01 00:01 [medline]
PHST- 1996/03/01 00:00 [entrez]
AID - 10.1111/j.1550-7408.1996.tb04496.x [doi]
PST - ppublish
SO  - J Eukaryot Microbiol. 1996 Mar-Apr;43(2):150-8. doi: 
      10.1111/j.1550-7408.1996.tb04496.x.