Dataset Information

Systems-level Analysis of Oxygen Exposure in Zymomonas mobilis: Implications for Isoprenoid Production

ABSTRACT: Zymomonas mobilis is an aerotolerant anaerobe and prolific ethanologen with attractive characteristics for industrial biofuel production. Here, we examine the effect of oxygen exposure on metabolism and gene expression in Z. mobilis by combining targeted metabolomics, mRNA sequencing, and shotgun proteomics. We found that exposure to oxygen profoundly influenced metabolism, inducing both transient metabolic bottlenecks and long-term metabolic remodeling. In particular, oxygen induced a severe but temporary metabolic bottleneck in the methyl erythritol 4-phosphate pathway for isoprenoid biosynthesis, likely caused by oxidative damage to the iron-sulfur co-factors of the final two enzymes of the pathway. This bottleneck was resolved with minimal changes in expression level of enzymes in the pathway but pronounced upregulation of enzymes related to iron-sulfur cluster maintenance and biogenesis (i.e. flavodoxin reductase and the suf operon). We also detected prominent changes in glucose utilization under aerobic conditions. Specifically, we observed increased gluconate production following exposure to oxygen, accounting for 18% of glucose uptake after 24 hours of aerobic growth. Our results suggest that under aerobic conditions, electrons from the oxidation of glucose to gluconate are delivered to the electron transport chain to minimize oxidative damage by reducing reactive oxygen species such as H2O2. This model is supported by the simultaneous upregulation of three membrane-bound dehydrogenases, cytochrome c peroxidase, and a cytochrome bd terminal oxidase.

OTHER RELATED OMICS DATASETS IN: GSE125123

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Zymomonas Mobilis

TISSUE(S): Permanent Cell Line Cell, Cell Culture

DISEASE(S): Disease Free

SUBMITTER: Alexander Hebert

LAB HEAD: Joshua Jacques Coon

PROVIDER: PXD011545 | Pride | 2019-01-18

REPOSITORIES: Pride

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			Action	DRS
	20170602_ASH_DN_ZYMO_ANA_A_INJ1_0.raw	Raw
	20170602_ASH_DN_ZYMO_ANA_A_INJ1_120.raw	Raw
	20170602_ASH_DN_ZYMO_ANA_A_INJ1_60.raw	Raw
	20170602_ASH_DN_ZYMO_ANA_B_INJ1_0.raw	Raw
	20170602_ASH_DN_ZYMO_ANA_B_INJ1_120.raw	Raw

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Systems-Level Analysis of Oxygen Exposure in <i>Zymomonas mobilis</i>: Implications for Isoprenoid Production.

Martien Julia I JI Hebert Alexander S AS Stevenson David M DM Regner Matthew R MR Khana Daven B DB Coon Joshua J JJ Amador-Noguez Daniel D

mSystems 20190101 1

Zymomonas mobilis is an aerotolerant anaerobe and prolific ethanologen with attractive characteristics for industrial bioproduct generation. However, there is currently insufficient knowledge of the impact that environmental factors have on flux through industrially relevant biosynthetic pathways. Here, we examined the effect of oxygen exposure on metabolism and gene expression in Z. mobilis by combining targeted metabolomics, mRNA sequencing, and shotgun proteomics. We found that exposure to ox ...[more]

PMID: 30801024

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