caa a22 4500 463186621 CHVBK 20180406164855.0 cr unu---uuuuu 170326e20071101xx s 000 0 eng 10.1007/s00726-006-0487-7 doi (NATIONALLICENCE)springer-10.1007/s00726-006-0487-7 The intramolecular δ15N of lysine responds to respiratory status in Paracoccus denitrificans [Elektronische Daten] [B. S. Pan, C. J. Wolyniak, J. T. Brenna] Summary.: Presented here is the first experimental evidence that natural, intramolecular, isotope ratios are sensitive to physiological status, based on observations of intramolecular δ15N of lysine in the mitochondrial mimic Paracoccus denitrificans. Paracoccus denitrificans, a versatile, gram-negative bacterium, was grown either aerobically or anaerobically on isotopically-characterized ammonium as sole cell-nitrogen source. Nitrogen isotope composition of the biomass with respect to source ammonium was $\Delta^{15}{\rm N}_{{\rm cell}-{\rm NH}_4}={{\delta}}^{15}{\rm N}_{{\rm cell}}-{{\delta}}^{15}{\rm N}_{{\rm NH}_4}$ = −6.2 ± 1.2‰ for whole cells under aerobic respiration, whereas cells grown anaerobically produced no net fractionation ( $\Delta^{15}{\rm N}_{{\rm cell}-{\rm NH}_4}$ = −0.3 ± 0.23‰). Fractionation of 15N between protein nitrogen and total cell nitrogen increased during anaerobic respiration and suggests that residual nitrogen-containing compounds in bacterial cell membranes are isotopically lighter under anaerobic respiration. In aerobic cells, the lysine intramolecular difference between peptide and sidechain nitrogen is negligible, but in anaerobic cells was a remarkable Δ15Np − s = δ15Npeptide − δ15Nsidechain = +11.0‰, driven predominantly by enrichment at the peptide N. Consideration of known lysine pathways suggests this to be likely due to enhanced synthesis of peptidoglycans in the anaerobic state. These data indicate that distinct pathway branching ratios associated with microbial respiration can be detected by natural intramolecular Δδ15N measurements, and are the first in vivo observations of position-specific measurements of nitrogen isotope fractionation. Springer-Verlag, 2007 Keywords: Intramolecular isotope ratio - 15N/14N, δ15N - Paracoccus denitrificans - Nitrogen metabolism nationallicence Pan B. S. Division of Nutritional Sciences, Cornell University, Ithaca, NY, U.S.A. aut Wolyniak C. J. Division of Nutritional Sciences, Cornell University, Ithaca, NY, U.S.A. aut Brenna J. T. Division of Nutritional Sciences, Cornell University, Ithaca, NY, U.S.A. aut Amino Acids Springer-Verlag 33/4(2007-11-01), 631-638 0939-4451 33:4<631 2007 33 726 https://doi.org/10.1007/s00726-006-0487-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00726-006-0487-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Pan B. S. Division of Nutritional Sciences, Cornell University, Ithaca, NY, U.S.A aut NATIONALLICENCE 700 1- Wolyniak C. J. Division of Nutritional Sciences, Cornell University, Ithaca, NY, U.S.A aut NATIONALLICENCE 700 1- Brenna J. T. Division of Nutritional Sciences, Cornell University, Ithaca, NY, U.S.A aut NATIONALLICENCE 773 0- Amino Acids Springer-Verlag 33/4(2007-11-01), 631-638 0939-4451 33:4<631 2007 33 726 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer