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The reproduction of microorganisms is defined as the increase in their number while maintaining the same cellular components. The doubling time of these cells varies widely depending on environmental factors and genetic factors inherent in each species. Vibrio natriegens, one of the fastest doubling microorganism, has been reported to double in less than 10 min in BHIN medium [1]. V. natriegens has been studied widely in order to understand this desirable characteristic of rapid cell division for industrial applications. The following genetic factors have been identified to contribute to rapid reproduction: 1) two chromosomes that can replicate independently and rapidly [2]; 2) a large number of rRNA operons (12 sets) that can perform translation efficiently; 3) localization of genes involved in transcription and translation near the bacterial origin of replication (oriC) to facilitate assembly of ribosomes; 4) rich in genes related to respiratory pathways that help in rapid cell growth [3]. Several following studies focus on the ways to leverage this species as a host for molecular biology and biotechnology applications [4,5].Corynebacterium glutamicum has been a useful industrial strain [6] for the production of biochemicals and recombinant proteins [7]. The doubling time of C. glutamicum in a defined CGXII medium without protocatechuate is known to be more than 2 h (corresponding growth rate = 0.34 h -1 ) [8]. Given that E. coli doubles every 0.9 h in glucose minimal medium [9], C. glutamicum grows much slower, which is disadvantageous for industrial use. To overcome this shortcoming and expand its applicability, adaptive laboratory evolution for accelerating the growth rate of C. glutamicum can be considered. Adaptive laboratory evolution has been used to Corynebacterium glutamicum, an important industrial strain, has a relatively slower reproduction rate. To acquire a growth-boosted C. glutamicum, a descendant strain was isolated from a continuous culture after 600 generations. The isolated descendant C. glutamicum, JH41 strain, was able to double 58% faster (t d =1.15 h) than the parental type strain (PT, t d =1.82 h). To understand the factors boosting reproduction, the transcriptomes of JH41 and PT strains were compared. The mRNAs involved in respiration and TCA cycle were upregulated. The intracellular ATP of the JH41 strain was 50% greater than the PT strain. The upregulation of NCgl1610 operon (a putative dyp-type heme peroxidase, a putative copper chaperone, and a putative copper importer) that presumed to role in the assembly and redox control of cytochrome c oxidase was found in the JH41 transcriptome. Plasmid-driven expression of the operon enabled the PT strain to double 19% faster (t d =1.82 h) than its control (t d =2.17 h) with 14% greater activity of cytochrome c oxidase and 27% greater intracellular ATP under the oxidative stress conditions. Upregulations of genes those might enhance translation fitness were also found in the JH41 transcriptome. Plasmid-driven expressions of NCgl0171 (encodin...

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Combination treatment with IFUS and TPIG has beneficial effects for skin lifting and tightening with early-onset time.