动物肠道中存在着一些参与猪肠道微生物互作的基因,这些基因具有一定的宿主特异性,利用其设计分子标记能准确识别粪便污染来源。该文共采集6个物种(猪、牛、羊、鸡、鸭、鹅)的145个粪便样品,提取其DNA后利用竞争性杂交的基因片段富集方...动物肠道中存在着一些参与猪肠道微生物互作的基因,这些基因具有一定的宿主特异性,利用其设计分子标记能准确识别粪便污染来源。该文共采集6个物种(猪、牛、羊、鸡、鸭、鹅)的145个粪便样品,提取其DNA后利用竞争性杂交的基因片段富集方法(genome fragment enrichment,GFE),靶向筛选参与猪肠道微生物互作的特异性基因。经BLASTX分析发现,82%的猪特异性非冗余DNA片段存在相似序列,以拟杆菌纲(Bacteroidetes)(43.2%)、梭菌纲(Clostridia)(19.5%)、芽孢杆菌纲(Bacilli)(8.6%)相似序列为主。从蛋白质功能方面分析,61.5%的非冗余序列功能明确,有7.6%的序列与信息贮存及加工有关,12.8%的序列与细胞加工及信息传导有关,22%的序列与代谢有关,其中,碳水化合物和氨基酸的转移代谢相关序列含量最为丰富,均占总特异性序列的6.3%。研究发现,能够编码拟杆菌纲(Bacteroidetes)和梭菌纲(Clostridials)等表面蛋白、膜分泌蛋白及碳水化合物代谢蛋白的相关基因可作为猪特异性分子标记筛选的靶点。展开更多
Mercury (Hg) concentrations in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five fish species (mullet Liza haematocheilus, flathead fish Platycephalus indicus, sea bass Lateolabrax japonicus, macke...Mercury (Hg) concentrations in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five fish species (mullet Liza haematocheilus, flathead fish Platycephalus indicus, sea bass Lateolabrax japonicus, mackerel Scomberomorus niphonius and silver pomfret Pampus argenteus) collected from Laizhou Bay in the Bohai Sea of China were investigated. The results indicate that Hg bioaccumulation in the five fish was tissue- specific, with the highest levels in the muscle and liver, followed by the stomach and gonads. The lowest levels were found in the gills and skin. Fish at higher trophic levels (flathead fish and sea bass) exhibited higher Hg concentrations than consumers at lower trophic levels. Mercury bioaccumulation tended to be positively correlated with fish length in mullet, silver pomfret, mackerel, and flathead fish, but was negatively correlated with fish length in sea bass. The Hg concentrations in the muscles of all fish species in Laizhou Bay were within the permissible limits of food safety set by national and international criteria. However, the suggesting maximum consumption of sea bass is 263g per week for human health.展开更多
文摘动物肠道中存在着一些参与猪肠道微生物互作的基因,这些基因具有一定的宿主特异性,利用其设计分子标记能准确识别粪便污染来源。该文共采集6个物种(猪、牛、羊、鸡、鸭、鹅)的145个粪便样品,提取其DNA后利用竞争性杂交的基因片段富集方法(genome fragment enrichment,GFE),靶向筛选参与猪肠道微生物互作的特异性基因。经BLASTX分析发现,82%的猪特异性非冗余DNA片段存在相似序列,以拟杆菌纲(Bacteroidetes)(43.2%)、梭菌纲(Clostridia)(19.5%)、芽孢杆菌纲(Bacilli)(8.6%)相似序列为主。从蛋白质功能方面分析,61.5%的非冗余序列功能明确,有7.6%的序列与信息贮存及加工有关,12.8%的序列与细胞加工及信息传导有关,22%的序列与代谢有关,其中,碳水化合物和氨基酸的转移代谢相关序列含量最为丰富,均占总特异性序列的6.3%。研究发现,能够编码拟杆菌纲(Bacteroidetes)和梭菌纲(Clostridials)等表面蛋白、膜分泌蛋白及碳水化合物代谢蛋白的相关基因可作为猪特异性分子标记筛选的靶点。
基金Supported by the National Natural Science Foundation of China for International or Regional Research Cooperation and Exchange Project(No.31061160187)the National Natural Science Foundation of China for Creative Research Group(No.41121064)
文摘Mercury (Hg) concentrations in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five fish species (mullet Liza haematocheilus, flathead fish Platycephalus indicus, sea bass Lateolabrax japonicus, mackerel Scomberomorus niphonius and silver pomfret Pampus argenteus) collected from Laizhou Bay in the Bohai Sea of China were investigated. The results indicate that Hg bioaccumulation in the five fish was tissue- specific, with the highest levels in the muscle and liver, followed by the stomach and gonads. The lowest levels were found in the gills and skin. Fish at higher trophic levels (flathead fish and sea bass) exhibited higher Hg concentrations than consumers at lower trophic levels. Mercury bioaccumulation tended to be positively correlated with fish length in mullet, silver pomfret, mackerel, and flathead fish, but was negatively correlated with fish length in sea bass. The Hg concentrations in the muscles of all fish species in Laizhou Bay were within the permissible limits of food safety set by national and international criteria. However, the suggesting maximum consumption of sea bass is 263g per week for human health.