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Pectinases have many applications in the industry of food, paper, and textiles, therefore finding novel polygalacturonases is required. Multiple sequence alignment and phylogenetic analysis of AnEPG (an endo-&#945;-1,4-polygalacturonase from <i>Aspergillus nidulans</i>) and other GH 28 endo-polygalacturonases suggested that AnEPG is different from others. AnEPG overexpressed in <i>Pichia pastoris</i> was characterized. AnEPG showed the highest activity at pH 4.0, and exhibited moderate activity over a narrow pH range (pH 2.0&#8722;5.0) and superior stability in a wide pH range (pH 2.0&#8722;12.0). It displayed the highest activity at 60 &#176;C, and retained &gt;42.2% of maximum activity between 20 and 80 &#176;C. It was stable below 40 &#176;C and lost activity very quickly above 50 &#176;C. Its apparent kinetic parameters against PGA (polygalacturonic acid) were determined, with the <i>K_m</i> and <i>k_cat</i> values of 8.3 mg/mL and 5640 &#956;mol/min/mg, respectively. Ba²⁺ and Ni²⁺ enhanced activity by 12.2% and 9.4%, respectively, while Ca²⁺, Cu²⁺, and Mn²⁺ inhibited activity by 14.8%, 12.8%, and 10.2% separately. Analysis of hydrolysis products by AnEPG proved that AnEPG belongs to an endo-polygalacturonase. Modelled structure of AnEPG by I-TASSER showed structural characteristics of endo-polygalacturonases. This pectinase has great potential to be used in food industry and as feed additives.