Differential Display Analysis Of Magnetic Spirillum MSR-1Magnetosome Gene Synthesis MRNA

The Magnetotactic bacterium (MTB) can generate magnetosome andrealize magnetotactic movement. Magnetosome is a kind of magnetic nanoparticlescoated by biomembrane. The synthesis of it is controlled by the genes of MTB. Theresearch of MTB mainly contains the growing environment and training mechanismof MTB, the synthesis, separation, purification and application of magnetosome.Among them, the synthesis of magnetosome is one of the most important parts. Atpresent, some genes and proteins related to magnetosome synthesis are separated.However, there are lots of genes related to magnetosome synthesis. It is important tofind and clone more genes related to magnetosome synthesis.This paper focused on Magnetospirillum gryphiswaldense, which is a kind ofmagnetotactic bacterium. Differential display method was applied to find the newgenes related to magnetosome synthesis. Different amounts of the medium wereadded in the same kind of containers. The conditions of magnetosome synthesis werecompared. The results were:40%bottle filling quantity could obtain the strainswhich can generate magnetosome.10%bottle filling quantity could obtain the strainswhich can’t generate magnetosome. The RNAs of the two kinds of strains wereextracted and the purity. Concentration and integrity of them were detected.Validation of primers was applied. RAP-PCR was done to the RNAs of the two kindsof strains separately by using primer1: CGCCGCCGCC and primer2:CCGCCGCCGC. Five different segments were obtained and named as M-1, M-2,M-3, M-4and M-5. Software was applied to predict the function of these differentsegments. The results were as follows：M-1encoding proteins were MSR-1unknownfunctional proteins. M-2speculated that the proteins have conserved domain rpoH2.The enzyme may activate transcription in specific position. Therefore, this proteinmight be identified as the enzyme of the initiation site of the magnetosome in MSR-1. The segment M-3and the segment M-4were speculated that the proteins containedconserved domains MqsR, and MqsR were the important regulators of the biofilmformation. Because the magnetosome is coated with a biofilm, it is speculated thatthis segment may be related to the formation of the magnetosome biofilm. SegmetM-5speculated that the proteins with domain PPK2and domain ALDH-SF. PPK2superfamily is one of the enzymes involved in the polyphosphate metabolism andoffer energy for cellular metabolism. ALDH-SF superfamily is the dependentaldehyde dehydrogenase superfamily. This enzyme contains three domains, a NAD(P)cofactor-binding domain, a catalytic domain and bridging domain. The NAD (P) inthe reduction of the NADH plays a catalytic role. NADH can provide energy for theferric reductase and ferric reductase in magnetosome formation process. Therefore,we speculated that segment M-5protein coding function may provide energy forMSR-1to production magnetosome.