{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T11:52:22Z","timestamp":1778586742927,"version":"3.51.4"},"reference-count":33,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,7,5]],"date-time":"2018-07-05T00:00:00Z","timestamp":1530748800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Grants from Southern Medical University","award":["B1040903"],"award-info":[{"award-number":["B1040903"]}]},{"name":"Grants from the Science and Technology Department of Guangdong Province of China","award":["2014A020210014"],"award-info":[{"award-number":["2014A020210014"]}]},{"name":"Grants from the Science and Technology Department of Guangdong Province of China","award":["2015A020211010"],"award-info":[{"award-number":["2015A020211010"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81773556"],"award-info":[{"award-number":["81773556"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81460545"],"award-info":[{"award-number":["81460545"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Actinobacteria are a phylum of bacteria known for their potential in producing structurally diversified natural products that are always associated with a broad range of biological activities. In this paper, using an H5N1 pseudo-typed virus drug screening system combined with a bioassay guided purification approach, an antiviral butanolide (1) was identified from the culture broth of Streptomyces sp. SMU03, a bacterium isolated from the feces of Elephas maximus in Yunnan province, China. This compound displayed broad and potent activity against a panel of influenza viruses including H1N1 and H3N2 subtypes, as well as influenza B virus and clinical isolates with half maximal inhibitory concentration values (IC50) in the range of 0.29 to 12 \u00b5g\/mL. In addition, 1 was also active against oseltamivir-resistant influenza virus strain of A\/PR\/8\/34 with NA-H274Y mutation. Studies on the detailed modes of action suggested that 1 functioned by interfering with the fusogenic process of hemagglutinin (HA) of influenza A virus (IAV), thereby blocking the entry of virus into host cells. Furthermore, the anti-IAV activity of 1 was assessed with infected BALB\/c mice, of which the appearance, weight, and histopathological changes in the infected lungs were significantly alleviated compared with the no-drug-treated group. Conclusively, these results provide evidence that natural products derived from microbes residing in animal intestines might be a good source for antiviral drug discovery.<\/jats:p>","DOI":"10.3390\/v10070356","type":"journal-article","created":{"date-parts":[[2018,7,5]],"date-time":"2018-07-05T10:52:44Z","timestamp":1530787964000},"page":"356","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Anti-Influenza A Viral Butenolide from Streptomyces sp. Smu03 Inhabiting the Intestine of Elephas maximus"],"prefix":"10.3390","volume":"10","author":[{"given":"Fangfang","family":"Li","sequence":"first","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"},{"name":"Guangdong Provincial Key Laboratory of Emergency Test for Dangerous Chemicals, Guangdong Provincial Public Laboratory of Analysis and Testing Technology, China National Analytical Center, Guangzhou 510000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daiwei","family":"Chen","sequence":"additional","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shengsheng","family":"Lu","sequence":"additional","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guang","family":"Yang","sequence":"additional","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoling","family":"Zhang","sequence":"additional","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhao","family":"Chen","sequence":"additional","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sheng","family":"Fan","sequence":"additional","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shaohua","family":"Wu","sequence":"additional","affiliation":[{"name":"Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan Institute of Microbiology, School of Life Sciences, Yunnan University, Kunming 650091, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jian","family":"He","sequence":"additional","affiliation":[{"name":"Group of peptides and natural products Research, School of Pharmaceutical Sciences, Southern Medical University, 1838 Guangzhou Avenue North; Guangzhou 510515, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,5]]},"reference":[{"key":"ref_1","first-page":"20150702","article-title":"Allometry of animal-microbe interactions and global census of animal-associated microbes","volume":"282","author":"Kieft","year":"2015","journal-title":"Proc. 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