Nematode-trapping fungi have been found to be natural killers of nematodes and their mechanisms might facilitate the development of new drugs or biological control agents, an Academia Sinica researcher said yesterday.
Mostly measuring less than 1mm, nematodes are found in soil worldwide and most are not visible to the naked eye, Academia Sinica Institute of Molecular Biology assistant research fellow Hsueh Yen-ping (薛雁冰) told a news conference in Taipei.
Some nematodes can cause infections in humans or damage plants, but existing pesticides, such as ivermectin, aldicarb and levamisole, can only inhibit their activity and the poisons’ efficacy are declining due to their wide use over the past few decades, she said.
Photo: CNA
Hsueh’s team found that oyster mushrooms, when starving, prey on nematodes by producing potent toxins that can paralyze them within minutes.
Using Caenorhabditis elegans as their model nematode, the team found that the fungal hyphae of oyster mushrooms trigger a massive calcium influx and rapid cell necrosis in the neuromuscular system of the nematode, making them more effective than nematicides, she said.
However, further research is needed to uncover the mushrooms’ key toxic compounds and if they might affect other creatures, she said.
The team detailed their findings in a paper published in the journal Proceedings of the National Academy of Sciences of the US on March 17. The paper, authored by Academia Sinica researchers, was listed as one of the issue’s cover stories.
Another paper by Hsueh, published a week later in the same journal, investigated a different mechanism found in nematode-trapping fungi that she said are present in more than two-thirds of soil samples collected in Taiwan.
Such fungi prey on almost all nematodes by sensing their pheromones, producing fungal hyphae to capture and decompose them, she said.
Genetic and genomic tools were used in the study, which also involved researchers from Cornell University and the University of California, Riverside, she added.
Having studied nematodes since her postdoctoral research at the California Institute of Technology a decade ago, Hsueh said she has long been fascinated by the interactions between nematodes and other organisms.
While literature about nematodes is limited, studying nematodes is essential to understanding the biogeochemistry of soil, as some nematodes might be beneficial to the environment like earthworms are, she said.
The nematode-killing mechanisms in the two studies suggest new routes for targeting parasitic nematodes infection in humans, animals and agriculture, Hsueh said, expressing the hope that her team would develop new treatments and biocontrol methods from the mechanisms.
Considering that most countries issue more than five denominations of banknotes, the central bank has decided to redesign all five denominations, the bank said as it prepares for the first major overhaul of the banknotes in more than 24 years. Central bank Governor Yang Chin-lung (楊金龍) is expected to report to the Legislative Yuan today on the bank’s operations and the redesign’s progress. The bank in a report sent to the legislature ahead of today’s meeting said it had commissioned a survey on the public’s preferences. Survey results showed that NT$100 and NT$1,000 banknotes are the most commonly used, while NT$200 and NT$2,000
The Centers for Disease Control (CDC) yesterday reported the first case of a new COVID-19 subvariant — BA.3.2 — in a 10-year-old Singaporean girl who had a fever upon arrival in Taiwan and tested positive for the disease. The girl left Taiwan on March 20 and the case did not have a direct impact on the local community, it said. The WHO added the BA.3.2 strain to its list of Variants Under Monitoring in December last year, but this was the first imported case of the COVID-19 variant in Taiwan, CDC Deputy Director-General Lin Ming-cheng (林明誠) said. The girl arrived in Taiwan on
South Korea is planning to revise its controversial electronic arrival card, a step Taiwanese officials said prompted them to hold off on planned retaliatory measures, a South Korean media report said yesterday. A Yonhap News Agency report said that the South Korean Ministry of Foreign Affairs is planning to remove the “previous departure place” and “next destination” fields from its e-arrival card system. The plan, reached after interagency consultations, is under review and aims to simplify entry procedures and align the electronic form with the paper version, a South Korean ministry official said. The fields — which appeared only on the electronic form
The Ministry of Foreign Affairs (MOFA) is suspending retaliation measures against South Korea that were set to take effect tomorrow, after Seoul said it is updating its e-arrival system, MOFA said today. The measures were to be a new round of retaliation after Taiwan on March 1 changed South Korea's designation on government-issued alien resident certificates held by South Korean nationals to "South Korea” from the "Republic of Korea," the country’s official name. The move came after months of protests to Seoul over its listing of Taiwan as "China (Taiwan)" in dropdown menus on its new online immigration entry system. MOFA last week