To clarify the meat type dependent distribution pattern of mobile genetic elements (MGEss)in sauced meat products.
A total of 20 samples from 5 brands were collected, including 5 samples each of beef, pork, chicken and duck. Metagenomic sequencing was performed, and the mobileOG database was employed to analyze MGEs composition, host sources and associated antimicrobial resistance genes and virulence factors.
A total of 2180 non-redundant MGEs genes were annotated. Braised pork exhibited the highest MGEs richness (1789 genes, of which 960 were pork-specific), while duck showed the lowest. Across the 4 groups, 1557 cross-group shared genes and 94 core MGEs genes were identified. Functionally, “replication/recombination/repair” genes predominated(40.6%). Pork showed significant enrichment in “integration/excision” (62.6%) and “transfer” (52.3%) functions. The expression levels of conjugative transfer (Tra) family genes, integrases and transposases in pork were 3.9–31.8-fold higher than those in other meat types, indicating the strongest MGEs-mediated genomic rearrangement and horizontal transfer activity in pork matrices. Toxin-antitoxin systems exhibited marked meat-type selectivity, with the Ccd system detected exclusively in chicken and pork. Microbial source tracking revealed that Enterococcus, Lactobacillus and Citrobacter were the core bacterial taxa driving MGEs diversity. Co-occurrence clusters of conjugative transfer-related MGEss were identified in pork sample P004, while Lactobacillus-associated MGEs co-occurrence clusters were found in P002, suggesting potential risks of antimicrobial resistance gene horizontal transfer and starter culture contamination during fermentation processing.
The distribution of MGEs in sauced meat products exhibits significant meat-type dependency, with the highest horizontal gene transfer activity observed in the pork matrix and Enterococcus spp. identified as the core driving microbiota; fermentation processes may introduce lactic acid bacteria-associated MGEs, thereby increasing the risk of antimicrobial resistance gene transfer.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |