Determination of bioremediation properties of soil-borne Bacillus sp. 5O5Y11 and its effect on the development of Zea mays in the presence of copper.

Today, industrial activities lead to the accumulation of heavy metals in the soil, water, and air due to mine deposits and operations, fertilizers, and drugs used in agriculture, and urban wastes. Using microorganism bioremediation of metals is an important technique in solving these problems. Herein, a rhizoid bacterium isolated from orchids that grow in Ovit plateau was defined as Bacillus sp. 5O5Y11 by conventional and molecular methods and the bioremediation properties of strain were investigated. It was capable of growth at high salt (10-15%) concentration, wide temperature (10-45 °C) and pH range (pH 4.5-8.0), and was observed to have strong lecithinase, gelatinase activity, and nitrate reduction. When the plant growth-promoting properties of this strain were examined, strong siderophore and ammonium production were observed in in vitro conditions. Bacillus sp. 5O5Y11 was found to have high tolerance to a group of heavy metals [iron (Fe), copper (Cu), lead (Pb), silver (Ag), zinc (Zn)]. Minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) values of copper metal on Bacillus sp. 5O5Y11 were determined as 12.5 mM and 50 mM, respectively. The effectiveness of this bacterium on the germination and growth of maize plant in the presence and absence of copper were investigated. These results suggest that Bacillus sp. 5O5Y11 is a microorganism, which has potential in metal bioremediation and plant growth promotion.

Molecular and in silico cloning, identification, and preharvest period expression analysis of a putative cytochrome P450 monooxygenase gene from Camellia sinensis (L.) Kuntze (tea).

Cytochrome P450 monooxygenases are one of the largest heme-containing protein groups, and the majority of them catalyze hydroxylation reactions dependent on nicotinamide adenine dinucleotide phosphate and oxygen. Cytochrome P450 (CYP) enzymes function in a wide range of monooxygenation reactions essential in primary and secondary metabolism in plants. Camellia sinensis (L.) Kuntze is a commercially and economically valuable plant due to its medicinally important secondary metabolites and as a beloved beverage. Cytochrome P450 monooxygenases play a significant role in the biosynthesis of a variety of secondary metabolites in tea. Although the biosynthesis of secondary metabolites has been investigated in detail, there have been limited studies conducted on identifying the genetic mechanisms of CYP-catalyzed secondary metabolic pathways in the C. sinensis (tea) plant. In our study, we characterized a putative C. sinensis (L.) Kuntze cytochrome P450 monooxygenase gene (Csp450), which has 1759 bp full-length cDNA with 49 bp of 5' and 183 bp of 3' untranslated regions. eTh CDS of the gene is 1527 bp and 508 amino acids in length. BLAST results of the deduced amino acid sequence revealed a high similarity with the CYP704C1-like superfamily. Preharvest period gene expression analysis from May, July, and September did not show any difference.

Exogenous hydrogen peroxide increases dry matter production, mineral content and level of osmotic solutes in young maize leaves and alleviates deleterious effects of copper stress.

BACKGROUND: The effects of exogenously applied H2O2 on growth, water status, the mineral ion content (Na+, K+, Ca2+, Mg2+ and Cu2+), proline, total sugars and soluble proteins were assessed in leaves of maize (Zea mays L.) cultivars, Akpinar and Pegaso exposed to excess copper (0.5 mM). Seedlings were grown in equal-sizes plastic pots and irrigated with Hoagland nutrient solution containing H2O2 or/and copper. Different treatments taken for pot experiments were named as the control (C), H2O2 treatment only (H2O2), excess Cu (Cu) and, Cu stress combined with H2O2 pretreatment (Cu + H2O2). RESULTS: Treatment of H2O2 caused the increases in growth, water content, mineral concentration, proline, total sugar and soluble protein contents compared to the control groups in the leaves of both cultivars. Yet excess copper caused reductions in the growth, leaf water potential, Na+, K+, Ca+, Mg2+ concentrations and soluble protein levels but increases in proline, total soluble sugars and Cu2+ contents compared to the control group. Dry matter, leaf water potential and mineral content of Cu + H2O2 group revealed a lower decrease than Cu group ones. A higher increase was also observed in proline and total sugar contents of Cu + H2O2 group than Cu group ones in both cultivars. CONCLUSIONS: These data revealed that exogenous H2O2 might increase the dry matter production and the mineral ion distribution in maize seedlings. Moreover, osmotic regulation might be involved in alleviation of copper toxicity of maize leaves by pretreatment of H2O2.