Diversity of bacterial strains degrading hexadecane in relation to the mode of substrate uptake

Abstract

M. BOUCHEZ-NAÏTALI, H. RAKATOZAFY, R. MARCHAL, J.-Y. LEVEAU AND J.-P.V AN DE C AS TE E LE . 1999. The relative distribution of the modes of hydrocarbon uptake, used by bacteria of the environment for the degradation of long-chain alkanes, has been evaluated. The first mode of uptake, direct interfacial accession, involves contact of cells with hydrocarbon droplets. In the second mode, biosurfactant-mediated transfer, cell contact takes place with hydrocarbons emulsified or solubilized by biosurfactants. Sixty-one strains growing on hexadecane were isolated from polluted and non-polluted soils and identified. The majority (61%) belonged to the CorynebacteriumMycobacterium-Nocardia group. Criteria selected for characterizing hexadecane uptake were cell hydrophobicity, interfacial and surface tensions and production of glycolipidic extracellular biosurfactants. These properties were determined in flask cultures on an insoluble (hexadecane) and on a soluble (glycerol or succinate) carbon source for a subset of 23 representative strains. Exclusive direct interfacial uptake was utilized by 47% of studied strains. A large proportion of strains (53%) produced biosurfactants. The data on cellular hydrophobicity suggested the existence of two distinct alkane transfer mechanisms in this group. Accordingly, tentative assignments of biosurfactant-mediated micellar transfer were made for 11% of the isolated strains, and of biosurfactant-enhanced interfacial uptake for 42%.

Catabolism of hydroxyacids and biotechnological production of lactones by Yarrowia lipolytica

“…Different mechanisms of entry have been described, mostly in bacteria, involving hydrophobic interactions or surfactant-mediated phenomena. They result in a mechanism of direct interfacial or surfactant-facilitated transport (Bouchez-Naïtali et al 1999. Some protrusion-forming structures resembling canals have been observed during the growth of C. tropicalis in alkane (Osumi et al 1975;Meisel et al 1976Meisel et al , 1977Tanaka and Fukui 1989).…”

Isolation and characterization of an n-hexadecane degrading Acinetobacter baumannii KSS1060 from a petrochemical wastewater treatment plant

“…Medium-chain alkanes are major soil contaminants, and among this class of alkanes, n-hexadecane (CH 3 (CH 2 ) 14 CH 3 ) has been used as a model contaminant of diesel oil by many researchers (Bouchez-Naitali et al 1999;Noordman et al 2002).…”

“…Medium-chain alkanes are the major soil contaminants, and among this class of alkanes, n-hexadecane (CH 3 (CH 2 ) 14 CH 3 ; 226.44 g mol -1 ) has been used as a model contaminant of diesel oil by many researchers (Bouchez-Naitali et al 1999;Noordman et al 2002) and has been chosen because of its low water solubility (0.9 lg l -1 ) (Dehghani et al 2013), as well as rapid degradability by numerous microorganisms (Dashti et al 2008). Hexadecane causes skin problems such as dryness, irritation, and cracking of skin, and when ingested can be harmful and even be fatal.…”

Impact of surfactants on the biotransformation of methyl ricinoleate into γ-decalactone by Yarrowia lipolytica

“…Due to the limited solubility of these hydrophobic substrates in water, growth occurs directly on fatty droplets in most of the cases [13] and the uptake can be directly interfacial or surfactant mediated [14,15]. Some authors have observed surface structures which might be involved in the uptake [16,17], structures which might also have an impact on the surface properties of the microorganisms and thus on the adhesion of fatty globules [15,18,19].…”