High-cell-density fed-batch cultivations of Vibrio natriegens

With generation times of less than 10 min under optimal conditions, the halophilic Vibrio natriegens is the fastest growing non-pathogenic bacterium isolated so far. The availability of the full genome and genetic engineering tools and its ability to utilize a wide range of carbon sources make V. natriegens an attractive host for biotechnological production processes. However, high-cell-density cultivations, which are desired at industrial-scale have not been described so far.

In this study we report fed-batch cultivations of V. natriegens in deep-well plates and lab-scale bioreactor cultivations at different temperatures in mineral salt medium (MSM). Upon switching from exponential glucose to constant glucose-feeding cell death was induced. Initial NaCl concentrations of 15-18 g L^-1 and a temperature reduction from 37 to 30 °C had a positive effect on cell growth. The maximal growth rate in MSM with glucose was 1.36 h^-1 with a specific oxygen uptake rate of 22 mmol g_CDW^-1 h^-1. High biomass yields of up to 55 g L^-1 after only 12 h were reached.

The shown fed-batch strategies demonstrate the potential of V. natriegens as a strong producer in industrial biotechnology.