Heme-degrading bacteria from blood-sucking organisms

Many ectoparasites that frequently change hosts, especially hematophagous parasites, often serve as vectors for pathogenic microorganisms and thus contribute to their transport and spread. The microbiome of these parasites can also contain pathogenic bacteria that can be transmitted on contact with the host. Especially in times of progressive climate change, which favors the spread of such parasitic vectors for pathogens, the precise research and associated prevention of such vector-borne infectious diseases and their bacteria is essential.

Since heme is a major component of the blood meal of these hematophagous parasites, the aim of this work is to investigate the different microbiomes of such parasites for heme-degrading bacteria, since these bacteria have to survive in an environment with a lot of, partly also toxic, free heme. The degradation and thus the potential utilization of heme also plays an important role for these pathogens in the case of infectious transmission into the bloodstream of a host.

The microbiome was extracted from leeches, ticks, mosquitoes and other bloodsuckers using various methods and individual bacterial strains were isolated and analyzed using Maldi Tof. Subsequently, these bacterial strains were examined for their ability to grow in heme-containing M9 medium with heme as the only carbon source.

Some bacteria showed no growth at all in this medium, others showed slightly increased growth with a slight but significant difference to the control without heme, which could indicate the utilization of heme. Genomic and proteomic studies of these strains will follow in the future to better elucidate the degradation and utilization pathway.