Reduction of chromium-VI by chromium-resistant Escherichia coli FACU: a prospective bacterium for bioremediation

Abstract The release of hexavalent chromium [Cr (VI)] into environments has resulted in many undesirable interactions with biological systems for its toxic potential and mutagenicity. Chromate reduction via chromium reductase (ChrR) is a key strategy for detoxifying Cr (VI) to trivalent species of no toxicity. In this study, ten bacterial isolates were isolated from heavily polluted soils, with a strain assigned as FACU, being the most efficient one able to reduce Cr (VI). FACU was identified as Escherichia coli based on morphological and 16S rRNA sequence analyses. Growth parameters and enzymatic actions of FACU were tested under different experimental conditions, in the presence of toxic chromium species. The E. coli FACU was able to reduce chromate at 100 μg/mL conceivably by reducing Cr (VI) into the less harmful Cr (III). Two distinctive optical spectroscopic techniques have been employed throughout the study. Laser-induced breakdown spectroscopy (LIBS) was utilized as qualitative analysis to demonstrate the presence of chromium with the distinctive spectral lines for bacteria such as Ca, Fe, and Na. While UV-visible spectroscopy was incorporated to confirm the reduction capabilities of E. coli after comparing Cr (III) spectrum to that of bacterial product spectrum and they were found to be identical. The chromate reductase specific activity was 361.33 μmol/L of Cr (VI) per min per mg protein. The FACU (EMCC 2289) 16S rRNA sequence and the ChrR-partially isolated gene were submitted to the DDBJ under acc. # numbers LC177419 and LC179020, respectively. The results support that FACU is a promising source of ChrR capable of bioremediation of toxic chromium species..

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:65

Enthalten in:

Folia microbiologica - 65(2020), 4 vom: 27. Jan., Seite 687-696

Sprache:

Englisch

Beteiligte Personen:

Mohamed, Mahmoud S.M. [VerfasserIn]
El-Arabi, Nagwa I. [VerfasserIn]
El-Hussein, Ahmed [VerfasserIn]
El-Maaty, Shereen Abu [VerfasserIn]
Abdelhadi, Abdelhadi A. [VerfasserIn]

Links:

Volltext [lizenzpflichtig]

Themen:

Bioremediation
Chromate reductase
Hexavalent chromium
LIBS

Anmerkungen:

© Institute of Microbiology, Academy of Sciences of the Czech Republic, v.v.i. 2020

doi:

10.1007/s12223-020-00771-y

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

OLC2118322208