Isolation, characterization, and quantification of Clostridium kluyveri from the bovine rumen

Abstract

A strain of Clostridium kluyveri was isolated from the bovine rumen in a medium containing ethanol as an electron donor and acetate and succinate (common products of rumen fermentation) as electron acceptors. The isolate displayed a narrow substrate range but wide temperature and pH ranges atypical of ruminal bacteria and a maximum specific growth rate near the typical liquid dilution rate of the rumen. Quantitative real-time PCR revealed that C. kluyveri was widespread among bovine ruminal samples but was present at only very low levels (0.00002% to 0.0002% of bacterial 16S rRNA gene copy number). However, the species was present in much higher levels (0.26% of bacterial 16S rRNA gene copy number) in lucerne silage (but not maize silage) that comprised much of the cows' diet. While C. kluyveri may account for several observations regarding ethanol utilization and volatile fatty acid production in the rumen, its population size and growth characteristics suggest that it is not a significant contributor to ruminal metabolism in typical dairy cattle, although it may be a significant contributor to silage fermentation. The ability of unadapted cultures to produce substantial levels (12.8 g L(-1)) of caproic (hexanoic) acid in vitro suggests that this strain may have potential for industrial production of caproic acid.

Mixed Carboxylic Acid Production by Megasphaera elsdenii from Glucose and Lignocellulosic Hydrolysate

“…This behavior is reflected in carboxylic acids productivities where~3-fold higher values were obtained in the pertractive system (0.26 g/L/h) compared to batch extractive (0.09 g/L/h). The pertractive productivity value in this work is the highest reported for the simultaneous production of VFAs using a mono-culture organism from sugars, greater than those obtained from sucrose 0.23 g/L/h [20] and glucose 0.13 g/L/h [21] considering both BA and HA or from acetate and ethanol 0.18 g/L/h [13] and galactitol 0.08 g/L/h [14] for exclusive HA production.…”

“…Choi et al [20] reached a combined BA and HA titer of 32.0 g/L from sucrose in liquid-liquid extractive fermentation also by M. elsdenii. Bacterial co-cultures and mono-culture fermentations of C. kluyveri using acetate and ethanol as carbon sources produced HA titers of < 10 and 12.8 g/L, respectively [13,15,18,19] and Clostridium sp. BS-1 has been reported to produce up to 32 g/L of HA in 16 days from galactitol.…”

Illuminating Anaerobic Microbial Community and Cooccurrence Patterns across a Quality Gradient in Chinese Liquor Fermentation Pit Muds

“…To detect the populations of Clostridia, C. kluyveri, and lactic acid bacteria (LAB) in an FPM sample, a quantitative PCR (qPCR) assay was used. The specific primer sets for Clostridia, C. kluyveri, and LAB were SJ-F/SJ-R (18), CloKly1F/CloKly1R (19), and Lac1/Lac2 (20), respectively. The real-time PCR calibration curves for quantifying the above-mentioned microbial taxa were generated via 10-fold serial dilutions of corresponding plasmids (see the text in the supplemental material).…”

Complete genome sequence of Ruminococcaceae bacterium CPB6: A newly isolated culture for efficient n -caproic acid production from lactate

“…It has been reported that a few strict anaerobic bacteria are capable of producing CA through fermentation. For example, Clostridium kluyveri can produce CA using ethanol as the electron donor (Barker and Taha, 1942;Kenealy et al, 1995;Weimer and Stevenson, 2012); Megasphaera elsdenii can produce CA from glucose and sucrose (Choi et al, 2013;Weimer and Moen, 2013); Clostridium sp. BS-1 produces CA using galactitol as the carbon source .…”