A kind of silac medium utilizing arginine-labeled bacteria and its preparation method and application

Abstract

The invention discloses a SILAC (stable isotope labeling by amino acids in cell culture) culture medium capable of labeling bacteria by using arginine as well as a preparation method and an application of the culture medium. The culture medium comprises inorganic salt, a carbon source, a nitrogen source, proline and heavy and stable isotope labeled arginine and further comprises glycine, alanine, valine, leucine, isoleucine, phenylalanine, proline, tryptophan, serine, tyrosine, cysteine, methionine, threonine, aspartic acid, glutamic acid, lysine, histidine and other amino acids as well as asparagine and glutamine. Proline is used, and heavy and stable isotope labeled arginine is prevented from being transformed into proline, so that the identification number and quantitative accuracy of protein are improved; another 19 common amino acids are added, the culture medium is complete in nutritional ingredient, thus, the culture medium is applicable to multiple bacteria, the bacteria grow rapidly in the culture medium, the labeling speed is high, and labeling can be completed in 1-3 generations; besides, the SILAC technology is applied to bacterial proteome and is simple to operate, good in repeatability and the like.

Description

technical field [0001] The invention relates to a culture medium, in particular to a SILAC culture medium using arginine to mark bacteria and its preparation method and application. Background technique [0002] Bacteria are a group with many types and numbers in nature. It is closely related to human activities. There are many bacteria that are pathogenic and even fatal. On the contrary, there are many bacteria that are beneficial, especially many engineered bacteria that serve human beings. At the same time, there are many probiotics in the human digestive tract that are helpful to human health. . Since the completion of the Human Genome Project, the genomes of many bacteria such as Escherichia coli have been sequenced and interpreted, which provides an opportunity for the development of proteomics. Proteomics can interpret life phenomena with all the proteins in a cell, which provides an effective means for finding drug targets, biological labels and understanding micro...

AI Technical Summary

Problems solved by technology

Proline containing heavy stable isotopes will change the mass of the peptide and change the mass-to-charge ratio of the peptide, resulting in the failure of the peptide to be identified, which will eventually lead to a decrease in the number of identified proteins and an increase in errors in protein quantification

Even, since amino acids can be used to synthesize the substances needed for their metabolism through the tricarboxylic acid cycle, if the heavy stable isotope labels arginine or lysine to synthesize other substances through the tricarboxylic acid cycle, the number of identified proteins will be even less , the quantification is more inaccurate

[0007] Based on the above reasons, SILAC can only use a single amino acid, namely lysine, as a labeled amino acid when it is used in bacteria

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