Name: mrsa: host adaptation and transmission
Uploaded: 2026-03-12T13:36:05.000Z
Duration: 1 min 25 s
Channel: JoVE

Oporność na antybiotyki to zdolność mikroorganizmu do wytrzymania działań antybiotyków.Powszechnie znany patogen, Staphylococcus aureus, rozwinął oporność na metycylinę, co skutkuje powstaniem Staphylococcus aureus, czyli MRSA, opornym na metycylinę.MRSA powoduje poważne infekcje skóry i tkanek miękkich u ludzi, co każdego roku prowadzi do milionów hospitalizacji i zgonów na całym świecie.Osoby starsze i immunosupresyjne są najbardziej narażone z powodu długotrwałego i intensywnego stosowania antybiotyków o szerokim spektrum spektrum.Strategie zwalczania MRSA obejmują stosowanie fitochemikaliów, terapię fagami, nanocząsteczki i probiotyki.Fitochemikalia — metabolity wtórne pozyskiwane z roślin — są szeroko stosowane do hamowania wzrostu MRSA.Specyficzne dla MRSA fagi mogą zmniejszyć populacje MRSA poprzez indukowanie lizy komórek.Nanocząstki wywierają naprężenie, uwalniając jony metali ciężkich w komórkach. Zmienia przepuszczalność błon i zakłóca niezbędne funkcje komórkowe.Wreszcie, niektóre szczepy probiotyków wydzielają związki przeciwdrobnoustrojowe, które hamują rozwój MRSA.

znaczenie kliniczne oporności na antybiotyki

Clinical Significance of Antibiotic Resistance

Gronkowec aureus (MRSA) oporny na metycylinę stanowi poważne zagrożenie dla zdrowia publicznego, wynikające z jego zdolności do odporności na antybiotyki β-laktamowe dzięki nabyciu genu mecA w chromosomie gronkowca kasetowego mec (SCCmec). Ten gen koduje białko wiążące penicylinę 2a (PBP2a), które zaburza skuteczność wiązania metycyliny i innych β-laktamów. MRSA ewoluowało w odrębne linie klonalne, wpływające zarówno na ludzi, jak i zwierzęta, wzmacniając swoje znaczenie w ramach paradygmatu One Health.Szczepy MRSA dzielą się na powiązane z opieką zdrowotną (HA-MRSA), związane ze społecznością (CA-MRSA) oraz związane ze zwierzętami hodowlanymi (LA-MRSA). Te linie wykazują zmienność kompleksu klonalnego (CC) oraz specyficzność gospodarza. Na przykład CC398 — początkowo pochodzenia ludzkiego — przeszedł adaptację u zwierząt gospodarskich, szczególnie świń, co doprowadziło do odwrotnego przenoszenia zoonotycznego. Zidentyfikowano wiele CC, takich jak CC1, CC5, CC8 i CC97, w różnych gatunkach gospodarzy, co wskazuje na złożony przepływ genów międzygatunkowych i adaptację środowiskową.Globalna częstość występowania MRSA jest bardzo zróżnicowana. Na przykład CA-MRSA stanowi 79% izolatów w Japonii, podczas gdy LA-MRSA wykryto u nawet 38,6% malezyjskiego bydła mlecznego. Kolonizacja LA-MRSA u zwierząt stanowi zagrożenie zoonotyczne, zwłaszcza dla osób w bliskim kontakcie, takich jak rolnicy i weterynarze. Raporty potwierdziły transmisje między zwierzętami domowymi a ludźmi, podkreślając potrzebę zintegrowanego nadzoru.Patogenność MRSA jest napędzana przez zestaw czynników zjadliwości, w tym MSCRAMMs, enterotoksyny oraz leukocydydę Panton-Valentine (PVL). Tworzenie biofilmu i fenol-rozpuszczalne moduliny dodatkowo zwiększają trwałość i unikanie odporności. Wyspy patogenności, takie jak SaPIbov, oraz mobilne elementy genetyczne, takie jak SCCmec typu XI, zawierające mecC, są kluczowe dla adaptacji gospodarza. Ponadto toksyna lukMF' , silnie eksprimowana w szczepach przystosowanych do bydła, nasila zapalenie mastitis u bydła mlecznego.Tradycyjne antybiotyki, w tym wankomycyna i daptomycyna, pozostają kluczowymi metodami leczenia, choć oporność nasila się. Nowe środki przeciwdrobnoustrojowe, takie jak tedizolid i delafloksacyna, wraz z podejściami nieantybiotycznymi — fitochemikaliami, probiotykami, nanocząsteczkami i bakteriofagami — dają obiecujące efekty. Warto zauważyć, że nanocząstki srebra syntetyzowane na zielono oraz szczepy probiotyczne Lactobacillus i Bifidobacterium wykazały istotną skuteczność in vitro przeciwko MRSA

Znaczenie kliniczne oporności na antybiotyki

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist &#946;-lactam antibiotics ...

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clinical-significance-of-antibiotic-resistance

Education

JoVE Core

Microbiology

Mikrobiologia

Unit

Jednostka

Antimicrobial Agents

Środki przeciwdrobnoustrojowe

KEY TERMS AND CONCEPTS

KLUCZOWE TERMINY I POJĘCIA

mrsa: host adaptation and transmission

MRSA, or methicillin-resistant Staphylococcus aureus, is a major public health threat. It resists beta-lactam antibiotics because it carries the mecA gene inside the staphylococcal cassette chromosome mec, or SCCmec. The mecA gene makes penicillin-binding protein 2a, which reduces how well methicillin and related beta-lactam drugs can bind.

MRSA has spread into separate clonal lineages that affect both humans and animals. These lineages fit the One Health idea, which links human, animal, and environmental health. MRSA is often grouped as healthcare-associated MRSA, community-associated MRSA, and livestock-associated MRSA. These groups also show different clonal complexes and host preferences.

One example is CC398. It began in humans, then adapted to livestock, especially pigs, and later spread back from animals to people. Other clonal complexes, including CC1, CC5, CC8, and CC97, have been found across host species. This pattern shows gene flow between species and adaptation to different environments.

MRSA prevalence also differs by region and host. Community-associated MRSA makes up 79% of isolates in Japan. Livestock-associated MRSA has been found in up to 38.6% of dairy cattle in Malaysia. Because LA-MRSA can colonize animals, it can also pose a zoonotic risk to people who work closely with them, such as farmers and veterinarians.

Transmission has also been reported between pets and humans. These findings show why integrated surveillance matters. MRSA pathogenicity is driven by virulence factors such as MSCRAMMs, enterotoxins, and Panton-Valentine leukocidin, or PVL. Biofilm formation and phenol-soluble modulins also help the bacteria persist and avoid immune attack.

Mobile genetic elements are important in host adaptation. SaPIbov and SCCmec type XI, which carries mecC, are examples. In bovine-adapted strains, the lukMF' toxin is strongly expressed and can worsen mastitis in dairy cattle. These features help explain how MRSA survives in different hosts and disease settings.

Treatment still relies on antibiotics such as vancomycin and daptomycin, but resistance is increasing. Newer drugs, including tedizolid and delafloxacin, may offer more options. Non-antibiotic strategies are also being studied, including phytochemicals, probiotics, nanoparticles, and bacteriophages. Green-synthesized silver nanoparticles and probiotic strains of Lactobacillus and Bifidobacterium have shown promising results against MRSA in laboratory studies.

MRSA: Host Adaptation and Transmission

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clinical significance of antibiotic resistance

MRSA, or methicillin-resistant Staphylococcus aureus, is a major public health threat. It resists beta-lactam antibiotics because it carries the mecA gene inside the staphylococcal cassette chromosome mec, or SCCmec. The mecA gene makes penicillin-binding protein 2a, which reduces how well methicillin and related beta-lactam drugs can bind. MRSA has spread into separate clonal lineages that affect both humans and animals. These lineages fit the One Health idea, which links human, animal, and...

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key terms and concepts

Learn how MRSA spreads between humans and animals, why it resists beta-lactam antibiotics, and what treatments and new control methods are being studied.

MRSA: Host Adaptation and Transmission | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

MRSA: Host Adaptation and Transmission

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