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Autotrophic acidophilic bacteria <i>Acidithiobacillus ferrooxidans</i> is a model species for studying metal bioleaching from low-grade sulfide ores and concentrates. Arsenopyrite gold-bearing concentrates are refractory and often processed using biohydrometallurgical approaches; therefore, it is important to develop methods to improve arsenopyrite bioleaching. In the present work, we have studied the possibility of improving arsenopyrite concentrate bioleaching by the strain of <i>A. ferrooxidans</i>. For this purpose, we have analyzed the genome of the strain <i>A</i>. <i>ferrooxidans</i> TFBk to reveal the genes potentially important in the bioleaching process. Genes determining resistance to arsenic, as well genes involved in the utilization of C₁-compounds and resistance to oxidative stress, were revealed. Therefore, the possibility of increasing the rate of arsenopyrite concentrate bioleaching using C₁-compounds (methanol and formate) was studied. Formate was able to increase both the biomass yield of the strain <i>A</i>. <i>ferrooxidans</i> TFBk as well as the bioleaching rate. In addition, the effect of redox potential increase by means of the addition of sodium persulfate in the medium on arsenopyrite concentrate bioleaching was studied. It was shown that the addition of 0.1% sodium persulfate stimulated strain growth, while a higher concentration inhibited it. Despite this, the rate of concentrate bioleaching increased in the presence of 0.5–1.0% of persulfate, which may be explained by the interactions of added oxidizer with concentrate components.