# Comparative studies for the biotechnological production of l-Lysine by immobilized cells of wild-type Corynebacterium glutamicum ATCC 13032 and mutant MH 20-22 B

## TL;DR

This paper compares the production of l-lysine using immobilized wild-type and mutant Corynebacterium glutamicum cells in a bioreactor.

## Contribution

The study introduces optimized conditions for lysine production using immobilized cells of a leucine auxotroph mutant strain.

## Key findings

- Optimal conditions for lysine production include 96 h fermentation, pH 7.5, 30°C, 90 g/l glucose, 1.0 vvm airflow, and 200 rpm agitation.
- The mutant strain C. glutamicum MH 20-22 B produced more l-lysine than the wild-type strain ATCC 13032 under the same conditions.
- Immobilized cells of the mutant strain showed higher productivity in aerobic bioprocesses.

## Abstract

Establishing a cost and time efficient approach for bioprocess optimization is desired but is challenging. In the present work, we have addressed the effectiveness of using immobilized cells for aerobic processes, behaviour of immobilized cells, optimization and upstream bioprocess analysis for the production of lysine by immobilized cells of Corynebacterium glutamicum ATCC 13032 and MH 20-22 B in stirred tank bioreactor. Optimized operational conditions for maximal yield and productivity were determined with six parameters i.e., pH, temperature, fermentation time, airflow rate, glucose concentration and aeration rate. With the obtained results, it was evident that the optimum values for the upstream parameters viz., fermentation time, pH, temperature, glucose concentration, air flow rate and agitation rate are 96 h, 7.5, 30 °C, 90 g/l, 1.0 vvm and 200 rpm for both immobilized cells of C. glutamicum ATCC 13032 and MH 20-22 B. Immobilized cells of C. glutamicum MH 20-22 B, which is a leucine auxotroph has yielded more l-lysine compare to the immobilized cells of wild type strain C. glutamicum ATCC 13032.