Assessing the effects of heavy metals in ACC deaminase and IAA production on plant growth-promoting bacteria.
This study poses a methodology in order to simultaneously quantify ACC deaminase and IAA levels in the same culture medium. Ten bacterial strains isolated from plant rhizosphere naturally settled in mining residues were chosen. These bacterial strains were characterized as PGPB, and all of them showed at least three characteristics (indole-3 acetic acid and siderophore production, ACC deaminase enzyme activity, and inorganic phosphate solubilization). Taxonomic identification showed that the strains belong to Enterobacter, Serratia, Klebsiella, and Escherichia genera. Similarly, both the ACC deaminase enzyme activity and the IAA synthesis in the presence of Cu, As, Pb, Ni, Cd, and Mn were measured. The results showed that both the ACC deaminase enzyme activity and the IAA synthesis were higher with the Pb, As, and Cu treatments than with the Escherichia N16, Enterobacter K131, Enterobacter N9, and Serratia K120 control treatments. On the other hand, Ni, Cd, and Mn negatively affected both the ACC deaminase enzyme activity and the IAA production on every bacterium except on the Klebsiella Mc173 strain. Serratia K120 bacterium got a positive correlation between ACC deaminase and IAA in the presence of every heavy metal, and it also promoted Helianthus annuus plant growth, showing a potential use in phytoremediation systems.
Benemérita Universidad Autónoma de Puebla, Facultad de Ingeniería Química, 104 4 Sur Street, Colonia Centro, Puebla, Zip 72000, Mexico. Electronic address: jcharlymh@yahoo.com.
Mendoza-Hernández José
MJ
Carlos
Colegio de Postgraduados, Orientación edafología, Carretera México-Texcoco Km 36.5, Montecillo, Texcoco, 56230 Estado de México, Mexico.
Perea-Vélez Yazmin
PY
Stefani
Benemérita Universidad Autónoma de Puebla, Facultad de Ingeniería Química, 104 4 Sur Street, Colonia Centro, Puebla, Zip 72000, Mexico.
Arriola-Morales
AM
Janette
Benemérita Universidad Autónoma de Puebla, Facultad de Ingeniería Química, 104 4 Sur Street, Colonia Centro, Puebla, Zip 72000, Mexico.
Martínez-Simón Sara
MS
Melani
Benemérita Universidad Autónoma de Puebla, Facultad de Ingeniería Química, 104 4 Sur Street, Colonia Centro, Puebla, Zip 72000, Mexico.
Pérez-Osorio
PO
Gabriela
D001419:Bacteria / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification / Q000378:metabolism*; D019755:Carbon-Carbon Lyases / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism*; D019216:Metals, Heavy / Q000633:toxicity*; D010937:Plant Growth Regulators / Q000378:metabolism*; D017262:Siderophores / Q000378:metabolism; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000633:toxicity*
D007210:Indoleacetic Acids; D019216:Metals, Heavy; D010937:Plant Growth Regulators; D017262:Siderophores; D012989:Soil Pollutants; C030737:indoleacetic acid; C033634:1-aminocyclopropane-1-carboxylate deaminase; D019755:Carbon-Carbon Lyases
Bioinoculators; Mining residues; Phytoremediation; Soil pollution