Quantification and Carbon and Nitrogen Isotopic Measurements of Heme B in Environmental Samples.
Anal Chem
; 92(16): 11213-11222, 2020 08 18.
Article
em En
| MEDLINE
| ID: mdl-32691593
ABSTRACT
Heme B is an iron-coordinated tetrapyrrole molecule that acts as a cofactor in hemoproteins. It is expected to be ubiquitous in the environment, as b-type hemoproteins catalyze a variety of essential biochemical reactions. In this study, we developed an analytical method to quantify heme B in biological and environmental samples using high-performance liquid chromatography (HPLC) coupled to a photodiode array detector. The applicability of our method was further extended by the use of liquid chromatography/mass spectrometry (LC/MS; detection limit â¼1 fmol), which enabled the quantification of a trace amount of dissolved heme B in filtered seawater and sedimentary heme B coexisting with an abundant interfering organic matrix. For compound-specific carbon and nitrogen isotopic measurements, heme B was successfully isolated and purified from biological and environmental samples by a combination of anion-exchange column chromatography, methyl esterification, and dual-step HPLC. While carbon and nitrogen isotopic compositions of heme B in phototrophs were mostly comparable to those of chlorophyll a, heme B in suspended particulate materials in coastal water and an intertidal sediment was 13C-depleted and 15N-enriched relative to chlorophyll a, suggesting that nonphototrophic microorganisms are also a significant source of heme B in natural environments.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água do Mar
/
Sedimentos Geológicos
/
Heme
Limite:
Animals
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article