Related Experiment Video
Updated: Jun 21, 2026
07:20
Bioprospecting of Extremophilic Microorganisms to Address Environmental Pollution
Published on: December 30, 2021
Paenibacillus macquariensis subsp. defensor subsp. nov., isolated from boreal soil.
Tamotsu Hoshino1, Takuto Nakabayashi, Kikue Hirota
1Research Institute of Genome-based Biofactory, National Institute of Advanced Industrial Science and Technology (AIST), Sapporo 062-8517, Japan.
Summary
Two novel bacterial strains, Paenibacillus macquariensis subsp. defensor, were discovered in Russian soil for their ability to combat a plant fungus. These findings expand the known diversity within the Paenibacillus genus.
Area of Science:
- Microbiology
- Bacteriology
- Plant Pathology
Background:
- Soil microorganisms play crucial roles in ecosystem health and plant defense.
- The fungus Typhula ishikariensis is a significant plant pathogen affecting crops.
- The genus Paenibacillus harbors diverse species with various ecological functions.
Purpose of the Study:
- To isolate and characterize novel bacterial strains from soil samples.
- To investigate the antagonistic activity of these isolates against the plant pathogen Typhula ishikariensis.
- To determine the taxonomic and phylogenetic placement of the novel isolates within the Paenibacillus genus.
Main Methods:
- Isolation of bacterial strains from soil samples.
- Phenotypic characterization, including morphology, Gram staining, and motility.
- Phylogenetic analysis using 16S rRNA gene sequencing.
- Chemotaxonomic analysis (fatty acid and isoprenoid quinone profiles).
- DNA-DNA hybridization and multilocus sequence analysis for taxonomic differentiation.
Main Results:
- Two bacterial strains, M4-2T and M4-1, were isolated and identified as Gram-variable, aerobic, motile rods.
- The isolates exhibited antagonistic activity against Typhula ishikariensis.
- Phylogenetic and chemotaxonomic analyses placed the isolates within the genus Paenibacillus.
- DNA-DNA hybridization and multilocus sequence analysis indicated that the isolates represent a novel subspecies, Paenibacillus macquariensis subsp. defensor.
Conclusions:
- The novel bacterial isolates, Paenibacillus macquariensis subsp. defensor, are proposed as a new subspecies.
- This discovery contributes to the understanding of bacterial diversity and their potential in biological control of plant pathogens.
- The findings highlight the importance of exploring soil microbial communities for novel biocontrol agents.
More Related Videos
09:49Prospecting Microbial Strains for Bioremediation and Probiotics Development for Metaorganism Research and Preservation
Published on: October 31, 2019
11:09Use of MALDI-TOF Mass Spectrometry and a Custom Database to Characterize Bacteria Indigenous to a Unique Cave Environment (Kartchner Caverns, AZ, USA)
Published on: January 2, 2015
Related Concept Videos
01:30Bacterial Phylum Actinobacteria
Coryneform bacteria are gram-positive, aerobic, nonmotile rods that exhibit irregular, club-shaped, or V-shaped arrangements. Their V-shape results from snapping division, where the inner cell wall layer forms the cross-wall, while the outer layer remains intact until it ruptures on one side, causing the daughter cells to bend away.The primary genera are Corynebacterium and Arthrobacter. Corynebacterium includes diverse species, ranging from saprophytes to pathogens like Corynebacterium...
01:18Other Unique Bacteria
Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic and are commonly found near the...
01:26Bacterial Phylum Proteobacteria
Proteobacteria, one of the largest and most diverse bacterial phyla, encompasses a wide range of Gram-negative bacteria distinguished by their outer membrane composed of lipopolysaccharides. These microorganisms exhibit various metabolic capabilities, including phototrophy, chemolithotrophy, and heterotrophy, and thrive in diverse environments from soil to aquatic systems and host-associated niches. The phylum is divided into six classes: Alphaproteobacteria, Betaproteobacteria,...
01:18Deep Sea Microbial Ecology
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches extending beyond...
01:25Clinical Significance of Antibiotic Resistance
Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
01:20Endospores and Sporulation
Endospores are specialized, dormant cells primarily formed by Gram-positive bacteria, including Bacillus and Clostridium, enabling survival under extreme environmental conditions. Due to their unique composition and formation process, these structures are highly resistant to physical and chemical insults, such as extreme heat, ultraviolet and ionizing radiation, desiccation, and toxic chemicals. Rare instances of endospore-like structures have also been observed in some Gram-negative bacteria,...