Endogenous nitric oxide in Pseudomonas fluorescens ZY2 as mediator against the combined exposure to zinc and cefradine

TY - JOUR

T1 - Endogenous nitric oxide in Pseudomonas fluorescens ZY2 as mediator against the combined exposure to zinc and cefradine

AU - Xu, Yan Bin

AU - Zhou, Yan

AU - Ruan, Jing Jing

AU - Xu, Shi Hui

AU - Gu, Ji Dong

AU - Huang, Shao Song

AU - Zheng, Li

AU - Yuan, Bao Hong

AU - Wen, Li Hua

N1 - Publisher Copyright: © 2015, Springer Science+Business Media New York.

PY - 2015/5/1

Y1 - 2015/5/1

N2 - A better understanding on the mechanism involved in bacterial resistance to combined exposure to antibiotics and heavy metals is helpful in implementing practices to mitigate their ecological risk and spread of resistance genes in microbial population. Pseudomonas fluorescens ZY2, a strain isolated from swine wastewater, was chosen to study its growth (bacterial density OD600), the formation of reactive oxygen species (ROS), nitric oxide (NO) and NO synthases (NOS) under Zn, cefradine or Zn + cefradine treatments. Using Zn and cefradine as representative heavy metal and antibiotic in this investigation, respectively, the resistance of P. fluorescens ZY2 to toxic chemical exposure was investigated. Bacterial densities of treatment groups significantly increased over the time of incubation, but less than the control. ROS, NO and NOS initially increased, but then decreased after the initial 8 h of culturing, and were positively related to Zn concentrations. Moreover, the formation of ROS, NOS, and NO was activated by cefradine at Zn of up to 160 mg/L, but inhibited at Zn of 200 mg/L whether cefradine was added or not. Zn concentration affected ROS and NO concentrations between treatments and also was closely related to the variation of the relative bacterial density. For P. fluorescens ZY2, the mediation of endogenous NO to overcome ROS in response to the combined exposure of Zn and cefradine was suggested as a co-resistance mechanism, which would be beneficial to evaluate the ecological risk of heavy metals and antibiotics.

AB - A better understanding on the mechanism involved in bacterial resistance to combined exposure to antibiotics and heavy metals is helpful in implementing practices to mitigate their ecological risk and spread of resistance genes in microbial population. Pseudomonas fluorescens ZY2, a strain isolated from swine wastewater, was chosen to study its growth (bacterial density OD600), the formation of reactive oxygen species (ROS), nitric oxide (NO) and NO synthases (NOS) under Zn, cefradine or Zn + cefradine treatments. Using Zn and cefradine as representative heavy metal and antibiotic in this investigation, respectively, the resistance of P. fluorescens ZY2 to toxic chemical exposure was investigated. Bacterial densities of treatment groups significantly increased over the time of incubation, but less than the control. ROS, NO and NOS initially increased, but then decreased after the initial 8 h of culturing, and were positively related to Zn concentrations. Moreover, the formation of ROS, NOS, and NO was activated by cefradine at Zn of up to 160 mg/L, but inhibited at Zn of 200 mg/L whether cefradine was added or not. Zn concentration affected ROS and NO concentrations between treatments and also was closely related to the variation of the relative bacterial density. For P. fluorescens ZY2, the mediation of endogenous NO to overcome ROS in response to the combined exposure of Zn and cefradine was suggested as a co-resistance mechanism, which would be beneficial to evaluate the ecological risk of heavy metals and antibiotics.

KW - Cefradine

KW - Nitric oxide (NO)

KW - Nitric oxide synthases (NOS)

KW - Reactive oxygen species (ROS)

KW - Zinc

UR - http://www.scopus.com/inward/record.url?scp=84939962038&partnerID=8YFLogxK

U2 - 10.1007/s10646-015-1428-6

DO - 10.1007/s10646-015-1428-6

M3 - 文章

C2 - 25678231

AN - SCOPUS:84939962038

SN - 0963-9292

VL - 24

SP - 835

EP - 843

JO - Ecotoxicology

JF - Ecotoxicology

IS - 4

ER -