The reported observations of an unidentified X-ray line feature at $sim$3.5 keV have driven a lively discussion about its possible dark matter origin. Motivated by this, we have measured the emph{K}-shell X-ray spectra of highly ionized bare sulfur ions following charge exchange with gaseous molecules in an electron beam ion trap, as a source of or a contributor to this X-ray line. We produce $mathrm{S}^{16+}$ and $mathrm{S}^{15+}$ ions and let them capture electrons in collision with those molecules with the electron beam turned off while recording X-ray spectra. We observed a charge-exchanged-induced X-ray feature at the Lyman series limit (3.47 $pm$ 0.06 keV). The inferred X-ray energy is in full agreement with the reported astrophysical observations and supports the novel scenario proposed by Gu and Kaastra (A & A textbf{584}, {L11} (2015)).
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