Related Experiment Video
Updated: Sep 19, 2025
09:47
Selective Cleaning of Wild Caenorhabditis Nematodes to Enrich for Intestinal Microbiome Bacteria
Published on: August 13, 2021
3.2K
Environmentally derived Balamuthia mandrillaris contains endosymbiotic bacteria
Kanako Yamanouchi1, Takamasa Nagai2, Takakiyo Tsujiguchi2
1Department of Bioscience and Laboratory Medicine, Graduate School of Health Sciences, Hirosaki University, 66-1 Hon-cho, Hirosaki, 036-8564, Japan. kanako.8@hirosaki-u.ac.jp.
Parasitology Research
|June 2, 2025
Summary
Balamuthia mandrillaris amoebas harbor viable, pigment-producing bacteria, including Chitinophaga, Inquilinus, and Brevundimonas. This bacterial symbiosis may enable amoeba survival in harsh, nutrient-poor environments.
Area of Science:
- Microbiology
- Environmental Science
- Amoebiasis Research
Background:
- Balamuthia mandrillaris, a free-living amoeba, causes fatal meningoencephalitis.
- Culturing B. mandrillaris is challenging due to endogenous bacterial contamination.
Purpose of the Study:
- To investigate the presence and identity of endogenous bacteria within B. mandrillaris.
- To understand the role of these bacteria in amoeba survival.
Main Methods:
- Isolation of two new B. mandrillaris strains from Japanese soil.
- Culture of amoebas under nutrient-free conditions for 60 days.
- Sequencing of endophytic bacteria within induced cysts.
Main Results:
- Viable bacteria were found within B. mandrillaris cysts after prolonged nutrient deprivation.
- Chitinophaga was common to both strains; Inquilinus and Brevundimonas were also detected.
- All identified bacteria were pigment-producing species.
Conclusions:
- B. mandrillaris harbors diverse, pigment-producing endophytic bacteria.
- Bacterial pigment production may facilitate B. mandrillaris survival in extreme, nutrient-limited conditions.
Related Concept Videos
01:26Bacterial Phylum Planctomycetes
95
Planctomycetes are a group of morphologically distinct bacteria predominantly classified into two orders: Planctomycetales and Brocadiales. These gram-negative bacteria exhibit unique features, including division by budding and the presence of stalks or appendages. Their cells are often found in rosette arrangements, and they are notable for possessing an S-layer in their cell envelope, which is relatively uncommon among bacteria. Additionally, Planctomycetes frequently exhibit intracellular...
95
01:29Bacterial Flora of the Large Intestine
661
The gut microbiome is formed by a vast and diverse community of bacteria that colonizes our large intestine. These bacteria start residing in the gut from birth and continue diversifying throughout life, influenced by factors such as diet, lifestyle, and stress. The gut bacterial community also includes bacteria from food and those that enter the colon through the anus.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
661
01:24Bacterial Phylum Tenericutes
103
The phylum Tenericutes, which includes the single class Mollicutes, comprises bacteria that lack cell walls. The term "Mollicutes" derives from the Latin word mollis, meaning "soft." These organisms are among the smallest known and are commonly referred to as mycoplasmas due to the prominence of the genus Mycoplasma, which includes well-known human pathogens. Despite their inability to stain gram-positively (a result of their lack of cell walls), mycoplasmas are phylogenetically related to the...
103
02:40Epiphytes, Parasites, and Carnivores
13.2K
Plants often form mutualistic relationships with soil-dwelling fungi or bacteria to enhance their roots’ nutrient uptake ability. Root-colonizing fungi (e.g., mycorrhizae) increase a plant’s root surface area, which promotes nutrient absorption. While root-colonizing, nitrogen-fixing bacteria (e.g., rhizobia) convert atmospheric nitrogen (N2) into ammonia (NH3), making nitrogen available to plants for various biological functions. For example, nitrogen is essential for the...
13.2K
01:15Diversity of Protists I
145
Excavata is a diverse group of protists that includes both chemoorganotrophic and phototrophic species, with some thriving in anaerobic environments. Among the key groups within Excavata are diplomonads and parabasalids, which are flagellated protists that lack mitochondria and chloroplasts. These microorganisms typically inhabit anoxic environments, such as the intestines of animals, where they exist either symbiotically or as parasites, relying on fermentation for energy production. Some...
145
01:26Bacterial Phylum Verrucomicrobiota
120
The phylum Verrucomicrobiota comprises at least four characterized orders, with most species classified within the order Verrucomicrobiotales. Members of this phylum are either aerobic or facultatively aerobic, with the ability to ferment sugars. A notable exception is the genus Methylacidiphilum, which consists of aerobic methanotrophs. Additionally, some Verrucomicrobiota establish symbiotic relationships with protists. These bacteria are widely distributed across various environments,...
120