Metabolomics Of Antarctica Rhodotorula Mucilaginosa AN5 Under Cadmium Stress By GC-MS Analysis

Antarctica has been covered with snow for a long time,which has been regarded as a pollution-free environment in people's mind.However,with the continuous expansion of human activities,the impact on the environment has become more and more extensive,and the real environmental situation of the Antarctic region is not optimistic.Metal pollution has caused serious effects on marine and soil.Under heavy metal stress,the contents of metabolites and metabolic pathways of microorganisms in marine and soil will change to some extent.In this paper,Rhodotorula mucilaginosa AN5 was used as the research object,and the metabolomics effects of Rhodotorula mucilaginosa AN5 under cadmium stress were studied by gas chromatography-mass spectrometry,aiming to analyze the interference of heavy metal cadmium to Rhodotorula mucilaginosa AN5 and the mechanism of yeast response to cadmium stress.(1)Rhodotorula mucilaginosa AN5 was cultured with nutrient-rich YEPD medium,and its growth curve was measured and its growth stage was analyzed.Rhodotorula mucilaginosa AN5 was inoculated into three heavy metal media with different cadmium concentrations,its growth curve was measured,and the logarithmic yeast was selected for subsequent metabolometrics experiments.The results were as follows: when yeast was growing in YEPD medium,its stability period was long and death period was almost invisible.After a very short delay period after inoculation,yeast rapidly enters into logarithmic growth,at which time the growth rate of yeast is faster.By calculating the growth inhibition rate,5 mmol/L,10 mmol/L and 20 mmol/L were selected as heavy metal culture medium,and the bacteria cultured to the logarithmic stage were taken for metabonomics analysis.(2)GC-MS technology was used for metabolomic analysis of Rhodotorula mucilaginosa AN5,and multi-dimensional statistical methods and bioinformatics software were used for data integration and in-depth analysis.The results were as follows: in the overall analysis of the four groups,QC samples were concentrated in the middle region,which proved that the sample repeatability was good.There was a significant separation between the 20 m M group and the other three groups,and there was a trend of separation between the 0 m M group and the 5 m M group and the 10 m M group,but there was no significant trend of separation between the 5 m M group and the10 m M group.In the grouping analysis,a differential metabolite was found in the 5 m M group and the 10 m M group,and there was no significant difference in the influence of the 5 m M group and the 10 m M group on yeast.In the pairwise comparison of other groups,it was found that the contents of various metabolites fluctuated.At the same time,the participation of the heavy metal cadmium in the metabolism of amino acids,sugars,nucleotides and other metabolic pathways in the body caused varying degrees of influence.By analyzing the changes of related metabolites and metabolic pathways of Rhodotorula mucilaginosa AN5 in different concentrations of cadmium,the resistance mechanism to heavy metal stress was explored,which provided a new perspective for the analysis and detection of Marine heavy metal pollution.