Donor plants were collected in spring from the area contaminated with heavy metals surrounding zinc smelter in the Silesia region in Poland. Soil was separated from roots by washing with sterile water (selection of rhizosphere bacteria). Roots were then disinfected with a solution of 70% ethanol for 3 min and then thoroughly washing them with sterile water. The root surfaces were then sterilized in 3% sodium hypochlorite for 0, 2.5, and 10 min and again washed with sterile water (endophytic bacteria isolation). Finally, roots were added with 0.9% NaCl (1:10) and macerated with mortar and pestle under sterile conditions. For tests 1 g of macerated tissue was placed in a tube containing 9 ml sterile 0.9% NaCl. Appropriate dilutions of tissue were prepared and next each dilution was then plated on 4 types of media: Congo Red agar (CRA, Sigma Aldrich, congo red acid morpholine propanesulfonicic acid pigmentation) or nitrogen-free base (NFb) solid media (mannitol 5 g; K2HPO4 0.6 g; KH2PO4 1.8 g; MgSO4•4H2O 0.2 g; NaCl 0.1 g; CaCl2•2H2O 0.2 g; bromothymol blue (BTB) 2 ml, vitamins 0.5 ml; microelements 1 ml, to isolate a free-living diazotrophic bacteria, Luria agar (LA) (Sigma Aldrich, L3272) to isolate nutritionally demanding bacteria, and yeast extract mannitol agar (YEMA) (Sigma Aldrich, Y3252) to isolate Rhizobiaceae bacteria. Plates were incubated at 30 ◦C for 2 (RCA, NFb, and LA) or 7 days (YEMA) to isolate bacteria. Evaluation morphology and mobility of each isolated bacterial strain was examinedby lightmicroscopy.Isolatedbacteria were tested for Gram coloration with a kit (Britania Laboratories) and for oxidase activity with disks (Britania Laboratories).