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Proteins of the MucR/Ros family play a crucial role in bacterial infection or symbiosis with eukaryotic hosts. MucR from <i>Sinorhizobium meliloti</i> plays a regulatory role in establishing symbiosis with the host plant, both dependent and independent of Quorum Sensing. Here, we report the first characterization of MucR isolated from <i>Sinorhizobium meliloti</i> by mass spectrometry and demonstrate that this protein forms higher-order oligomers in its native condition of expression by SEC-MALS. We show that MucR purified from <i>Sinorhizobium meliloti</i> can bind DNA and recognize the region upstream of the <i>ndvA</i> gene in EMSA, revealing that this gene is a direct target of MucR. Although MucR DNA binding activity was already described, a detailed characterization of <i>Sinorhizobium meliloti</i> DNA targets has never been reported. We, thus, analyze sequences recognized by MucR in the <i>rem</i> gene promoter, showing that this protein recognizes AT-rich sequences and does not require a consensus sequence to bind DNA. Furthermore, we investigate the dependence of MucR DNA binding on the length of DNA targets. Taken together, our studies establish MucR from <i>Sinorhizobium meliloti</i> as a member of a new family of Histone-like Nucleoid Structuring (H-NS) proteins, thus explaining the multifaceted role of this protein in many species of alpha-proteobacteria.