In this study,the bacteria from the mud in tidal-flat Sinonovacula constricta aquaculture area were isolated each month from March to December,2002,and the temporal and spatial distribution of heterotrophic bacteria,a...In this study,the bacteria from the mud in tidal-flat Sinonovacula constricta aquaculture area were isolated each month from March to December,2002,and the temporal and spatial distribution of heterotrophic bacteria,ammonifying bacteria,denitrifying bacteria,and sulphate reducing bacteria were analyzed.The results showed that all the 515 isolated bacteria mainly belonged to 1 family and 13 genera.The bacterial flora in different layers of the mud was almost consistent,while the composition was different.The predominant genera were Clostridium,Bacillus,Corynebacterium,Photobacterium,and some Enterobacteriaceae.The number of heterotrophic bacteria in the surface layer and the bottom fluctuated in 7.6×103 cfu·g-1～2.0×105 and 1.6×103～1.0×105 cfu·g-1,ammonifying bacteria fluctuated in 1.5×106～9.0×107 and 9.0×105～1.0×107 cfu·g-1,denitrifying bacteria fluctuated in 9.0×103～4.0×106 and 5.0×102～1.9×106 cfu·g-1,and sulphate reducing bacteria fluctuated in 5.0×104～5.0×106 and 1.9×104～2.0×106 cfu·g-1,respectively.The detection rates of ammonifying bacteria,denitrifying bacteria and sulphate reducing bacteria in the mud were all 100%,and these bacteria increased significantly in the second half of the year,indicating that the environment of the Sinonovacula constricta aquaculture area was deteriorated due to the accumulation of NH3,nitrite and H2S,and it is important to regulate the breed capacity and redistribute the breeding environment.展开更多
文摘在水产养殖领域,对厚壳贻贝(Mytilus coruscus)的生长发育机制进行深入探讨,可为实现生长发育分子调控奠定理论基础。为了探究厚壳贻贝幼虫生长与发育差异基因的表达模式,本研究采用转录组测序和实时荧光定量PCR分析技术,对与生长特征相关的基因和分子途径的表达差异进行了初步研究。研究重点关注哺乳动物雷帕霉素靶蛋白(mammalian Target Of Rapamycin,mTOR)信号通路在厚壳贻贝幼虫生长和发育中的影响及调节作用。通过对不同发育时期(担轮幼虫期、D形幼虫期、壳顶幼虫期、眼点幼虫期和稚贝期)的基因表达模式进行分析,结果表明mTOR信号通路可能在厚壳贻贝幼虫的生长发育中扮演一定角色,并成功鉴定出7个与生长发育相关的关键基因。随着发育过程的推进,mTOR信号通路基因在不同发育时期的表达呈现出动态变化。其中,PI3K、TSC1/2和mTOR基因的整体表达变化趋势为先上升后下降再上升,IGFI变化趋势为先上升后下降,而EIF4B、RPS6KB和AKT基因表达则整体呈现下降趋势。这一差异化的基因表达模式反映了mTOR信号通路可能在厚壳贻贝幼虫不同发育时期中对细胞命运和生物学功能的调控,从而对其生长发育产生影响。因此,我们对mTOR信号通路关键基因在厚壳贻贝幼虫生长发育中的表达模式进行了初步探究。这些基因在调控厚壳贻贝幼虫的分子功能和生长特征方面具有重要作用,为深入理解海洋双壳动物的生理适应、代谢过程和生长变异提供了基础数据。
文摘In this study,the bacteria from the mud in tidal-flat Sinonovacula constricta aquaculture area were isolated each month from March to December,2002,and the temporal and spatial distribution of heterotrophic bacteria,ammonifying bacteria,denitrifying bacteria,and sulphate reducing bacteria were analyzed.The results showed that all the 515 isolated bacteria mainly belonged to 1 family and 13 genera.The bacterial flora in different layers of the mud was almost consistent,while the composition was different.The predominant genera were Clostridium,Bacillus,Corynebacterium,Photobacterium,and some Enterobacteriaceae.The number of heterotrophic bacteria in the surface layer and the bottom fluctuated in 7.6×103 cfu·g-1～2.0×105 and 1.6×103～1.0×105 cfu·g-1,ammonifying bacteria fluctuated in 1.5×106～9.0×107 and 9.0×105～1.0×107 cfu·g-1,denitrifying bacteria fluctuated in 9.0×103～4.0×106 and 5.0×102～1.9×106 cfu·g-1,and sulphate reducing bacteria fluctuated in 5.0×104～5.0×106 and 1.9×104～2.0×106 cfu·g-1,respectively.The detection rates of ammonifying bacteria,denitrifying bacteria and sulphate reducing bacteria in the mud were all 100%,and these bacteria increased significantly in the second half of the year,indicating that the environment of the Sinonovacula constricta aquaculture area was deteriorated due to the accumulation of NH3,nitrite and H2S,and it is important to regulate the breed capacity and redistribute the breeding environment.
