Growth and Polysaccharide Production by Methylocystis parvus OBBP on Methanol

Abstract

Methylocystis parvus OBBP, an obligate methylotroph originally isolated as a methane-utilizing bacterium, was cultivated on methanol as a sole source of carbon. After adaptation to high methanol levels, this organism grew on methanol with a maximum specific growth rate of 0.65 h-1. The pH optimum for growth was between 7 and 9, and the temperature optimum was between 30 and 37°C. Methanol concentrations higher than 5% (by weight) were toxic. Formaldehyde, at a concentration greater than 1 mM, inhibited growth. Formate was neither a substrate nor an inhibitor. An extracellular viscous heteropolysaccharide was produced during growth. The maximum production of the total biomass was 14.5 g (dry weight) per liter of broth. The dried biomass contained 22% (wt/wt) crude protein and 62% (wt/wt) polysaccharide. The main components of the polysaccharide were D-glucose (82%) and L-rhamnose (14%).

Bacterial communities in manganese nodules in rice field subsoils: Estimation using PCR-DGGE and sequencing analyses

“…Bands A2, A3 and A4 were closely related to methane‐oxidizing bacteria of Methylococcus capsulatus (Dedysh et al . 2004), Methylocystis parvus (Hou et al . 1979) and Methylosinus trichosporium (Bowman et al .…”

Cultivation of methanotrophic bacteria in opposing gradients of methane and oxygen

“…So far, formaldehyde production (0.2-7 mM) by methanotrophs was reported only during growth at high methanol and oxygen concentrations (Agrawal & Lim, 1984;Costa et al, 2001). Formaldehyde becomes inhibitory at concentrations between 1 mM (Hou et al, 1978) and 7 mM (Costa et al, 2001). Thus, the amount of formaldehyde produced by strain LC 2 (up to 1 mM) could be sufficient to inhibit growth of this bacterium, and other strains might be even more sensitive to this toxic compound.…”

“…Thus, the amount of formaldehyde produced by strain LC 2 (up to 1 mM) could be sufficient to inhibit growth of this bacterium, and other strains might be even more sensitive to this toxic compound. Methanotrophs are known to produce copious amounts of exopolymeric substances (EPS) (Hou et al, 1978;Linton et al, 1986). For mixed MOB cultures in compost, the highest EPS production was reported at high oxygen levels (10.5% vs. 1.5% O 2 ) (Wilshusen et al, 2004).…”

A methane‐driven microbial food web in a wetland rice soil

“…CO 2 from methane oxidation may be assimilated by autotrophs (Bosse and Frenzel, 1997; Raghoebarsing et al ., 2005). Depending on growth conditions, methanotrophs may produce exopolymeric substances (Hou et al ., 1979; Wilshusen et al ., 2004) or release metabolites, e.g. formaldehyde (Bussmann et al ., 2006); both may serve as substrates for other microorganisms.…”