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Journal ArticleDOI

Aspects of culture:Acanthamoeba astronyxis (Ray and Hayes 1954) from Bay of Bengal coasts, India

01 Jan 1987-Vol. 96, Iss: 1, pp 63-69
TL;DR: The overall growth showed little variation over ranges of media salinity (5–30‰), however, greater values were encountered in media of intermediate range, while mid-littoral and lowest low tide isolates preferred bay water agar and saline distilledWater agar media more.
Abstract: Acanthamoeba astronyxis strains, isolated from intertidal belts of Sagar Island (21°30′ to 21°50′ N and 88°04′ to 88°08′ E) facing Bay of Bengal, were cultured in saline distilled water agar medium supplemented withEscherichia coli as food bacterium. Population growth in bay water agar, cerophyl bay water agar and soil extract distilled water agar were compared with special reference to devised saline distilled water agar medium. The overall growth showed little variation over ranges of media salinity (5–30‰). However, greater values were encountered in media of intermediate range. Isolate from mangrove litter-soil of highest high tide belt (strains) grew more efficiently in cerophyl bay water agar and soil extract distilled water agar media while mid-littoral and lowest low tide isolates preferred bay water agar and saline distilled water agar media more.
Citations
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Book ChapterDOI
15 Mar 2013

8 citations

Journal ArticleDOI
TL;DR: It has been found that the overall number of organisms per gram of soil attains peak value during the monsoon period, and this value comes down in post-monsoon samples and is the least in pre- monsoon ones.
Abstract: Acanthamoeba rhysodes has been found to be a predominant intertidal benthic gymnamoeba in the mangrove ecosystem of Sundarbans of lower deltaic Bengal, facing the Bay. The sampling zones under study were the highest high tide regions, with characteristic mangrove litter-soil, inundated twice per month during the highest ebb of spring tide. Population abundance of this species, both in its trophic and cystic forms in the three distinct seasonal periods of pre-monsoon (March to June), monsoon (July to October), and post-monsoon (November to February) has been surveyed for over two years. These seasonal periods affect the physico-chemical parameters of the habitat substrata, including temperature, pH, and salinity. It has been found that the overall number of organisms per gram of soil attains peak value during the monsoon period. This value comes down in post-monsoon samples and is the least in pre-monsoon ones.

7 citations

References
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Journal ArticleDOI
TL;DR: Four clonal strains of amoebae isolated from salt-water habitats of the Maine coast show the characteristic Nebenkorper or paranucleus of the genus Paramoeba Schaudinn, 1896, this being the first report of free-living members of that genus from North America.
Abstract: SYNOPSIS Four clonal strains of amoebae isolated from salt-water habitats of the Maine coast show the characteristic Nebenkorper or paranucleus of the genus Paramoeba Schaudinn, 1896, this being the first report of free-living members of that genus from North America. The isolates are identified as 2 species, P. pemaquidensis n. sp. and P. aestuarina n. sp. In form and mitotic pattern, these 2 species resemble members of the family Mayorellidae.

45 citations

Journal ArticleDOI
TL;DR: Redox potential and pH determinations revealed that the mixed fluid cultures were aerobic and the amoebae perished at pH values more acid than 5·6, and permanent cultures were maintained with Aerobacter aerogenes, Escherichia coli, 8 species of Salmonella and 2 of Shigella.
Abstract: A flagellate amoeba, isolated from Ohio River water and identified as Naegleria gruberi (Schardinger), has been maintained in permanent cultures on a buffered sucrose nitrate agar with its original bacterial associate, identified as Proteus mirabilis. On Czapek agar plates, the growth curve of the amoeba at 25-27° was found to consist of a lag phase of about 4 hr., a log growth phase of about 60 hr., and a growth-encystment phase of 2-3 weeks. At 37° the lag phase was shortened by half and the log growth phase by about a third. The generation time was 4 1/2 hr. at 25-27° and 2 1/2 hr. at 37°. Continuous cultivation at 37°, however, resulted in occurrence of abnormal forms. Very poor growth of amoeba on nutrient and tryptose agars was attributed to their high organic nitrogen content, poor growth in liquid media to the difficulty of amoebae to engulf bacteria. Attempts to grow the amoeba on heat-killed bacteria were failures. Redox potential and pH determinations revealed that the mixed fluid cultures were aerobic and the amoebae perished at pH values more acid than 5·6. Replacement of Proteus mirabilis by other bacteria by Oehler's technique was unsuccessful because of swarming but was successful with a Flavobacterium sp., which produced a yellow pigment whose antibiotic effect prevented swarming. Permanent cultures of the amoeba with the new bacterial associate were maintained after the amoeba overcame the antibiotic effect of the pigment. Replacement of the Flavobacterium sp. in the mixed culture by new species of bacteria was easily accomplished, and permanent cultures were maintained with Aerobacter aerogenes, Escherichia coli, 8 species of Salmonella and 2 of Shigella. The amoebae encysted earlier on all these species than on Proteus mirabilis. Cytological observations include: (a) appearance of the chromatin material as short rods; (b) no evidence of thread-like structures radiating from the karyosome or chromatin patches in resting nucleus, nor the centrioles in mitosis; (c) karyosome origin of both the ‘interzonal body’ and the polar caps.

35 citations

01 Jan 1979
TL;DR: In this paper, the authors present a key to 15 families of freshwater and marine amoebae, of which only one, the Echinamoebidac, does not contain a known marine species.
Abstract: This manual contain8 a key to 15 families of freshwater and marine amoebae, of which only one, the Echinamoebidac, docs not contain a known marine species. Diagnostic features for 49 genera, of which 34 include marine species, also are given. Descriptions and illustrations for 76 species of marine amoebae and an annotated systematic list are provided. The basic key is designed to assist the user in the identification ofrecognizcd species of marine amoebae that have been described from waters of the northeastern United States. However, certain well-known families and genera of freshwater forms are included to assist in thci'r identification should they be discovered in seawater in future investigations. Information also is provided which includes comments on the general biology of the Amoebida, and techniques for microscopic observations and laboratory cultivation of many species. Most of the amoebae described in the key are free living, but a few are parasitic al1d known to be of considerable economic importance. One new free-living species, Vexillifera minutissima, was discovered in Chincoteague Bay, Va., and is described herein for the first time.

33 citations

Journal ArticleDOI
TL;DR: All six species studied with the electron microscope have the characteristic surface structure found also in freshwater members of the genus Vannella Bovee, which is probably their main food in nature.
Abstract: A key to all nine described marine species of naked lobose amoebae classified in the genus Vannella Bovee , 1965, is presented. All six species studied with the electron microscope have the characteristic surface structure found also in freshwater members of the genus. The key includes five species isolated from British waters, including three new species; a fourth new species is from the Persian Gulf area. Generic identification of Vannella , even in mixed material, can be made readily with the electron microscope, which is sometimes necessary for positive distinction from Platyamoeba . Further identification to species is a light-microscopical procedure. Members of this genus are cultured on bacteria, which are probably their main food in nature.

23 citations