title: Poly(3-hydroxybutyrate) anabolism in Cupriavidus necator cultivated at various carbon-to-nitrogen ratios: insights from single-cell Raman spectroscopy.
abstract: Cupriavidus necator accumulates large amounts of poly(3-hydroxybutyrate) (PHB), a biodegradable substitute for petroleum-based plastics, under certain nutrient conditions. Conventional solvent-extraction-based methods for PHB quantification only obtain average information from cell populations and, thus, mask the heterogeneity among individual cells. Laser tweezers Raman spectroscopy (LTRS) was used to monitor dynamic changes in the contents of PHB, nucleic acids, and proteins in <italic<C. necator</italic< at the population and single-cell levels when the microorganism cells were cultivated at various carbon-to-nitrogen ratios. The biosynthetic activities of nucleic acids and proteins were maintained at high levels, and only a small amount of PHB was produced when the bacterial cells were cultured under balanced growth conditions. By contrast, the syntheses of nucleic acids and proteins were blocked, and PHB was accumulated in massive amount inside the microbial cells under nitrogen-limiting growth circumstances. Single-cell analysis revealed a relatively high heterogeneity in PHB level at the early stage of the bacterial growth. Additionally, bacterial cells in populations at certain cultivation stages were composed of two or three subpopulations on the basis of their PHB abundance. Overall, LTRS is a reliable single-cell analysis tool that can provide insights into PHB fermentation.
authors.affiliation: Guangxi Academy of Sciences, Laboratory of Biophysics, 98 Daling Road, Nanning, Guangxi 530007, China.
authors.forename: Zhanhua
authors.initials: Z
authors.lastname: Tao
authors.affiliation: Washington University in St. Louis, Department of Biomedical Engineering, Optical Imaging Laboratory, One Brookings Drive, Campus Box 1097, St. Louis, Missouri 63130, United States.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Guangxi Academy of Sciences, Laboratory of Biophysics, 98 Daling Road, Nanning, Guangxi 530007, China.
authors.forename: Zhaojun
authors.initials: Z
authors.lastname: Qin
authors.affiliation: East Carolina University, Department of Physics, East 5th Street, Greenville, North Carolina 27858, United States.
authors.forename: Yong-Qing
authors.initials: YQ
authors.lastname: Li
authors.affiliation: Guangxi Academy of Sciences, Laboratory of Biophysics, 98 Daling Road, Nanning, Guangxi 530007, China.
authors.forename: Guiwen
authors.initials: G
authors.lastname: Wang
mesh_terms: D002244:Carbon / Q000032:analysis / Q000378:metabolism; D020118:Cupriavidus necator / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism*; D005285:Fermentation; D006885:Hydroxybutyrates / Q000032:analysis / Q000378:metabolism*; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism; D052898:Optical Tweezers; D011091:Polyesters / Q000032:analysis / Q000378:metabolism*; D059010:Single-Cell Analysis / Q000379:methods*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D000094122:Polyhydroxybutyrates
chemical_list: D002244:Carbon; D006885:Hydroxybutyrates; D009584:Nitrogen; D011091:Polyesters; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates