Improving the acetic acid tolerance and fermentation of Acetobacter pasteurianus by nucleotide excision repair protein UvrA

Abstract

Acetic acid bacteria (AAB) are widely used in acetic acid fermentation due to their remarkable ability to oxidize ethanol and high tolerance against acetic acid. In Acetobacter pasteurianus, nucleotide excision repair protein UvrA was up-regulated 2.1 times by acetic acid when compared with that without acetic acid. To study the effects of UvrA on A. pasteurianus acetic acid tolerance, uvrA knockout strain AC2005-ΔuvrA, uvrA overexpression strain AC2005 (pMV24-uvrA), and the control strain AC2005 (pMV24), were constructed. One percent initial acetic acid was almost lethal to AC2005-ΔuvrA. However, the biomass of the UvrA overexpression strain was higher than that of the control under acetic acid concentrations. After 6% acetic acid shock for 20 and 40 min, the survival ratios of AC2005 (pMV24-uvrA) were 2 and 0.12%, respectively; however, they were 1.5 and 0.06% for the control strain AC2005 (pMV24). UvrA overexpression enhanced the acetification rate by 21.7% when compared with the control. The enzymes involved in ethanol oxidation and acetic acid tolerance were up-regulated during acetic acid fermentation due to the overexpression of UvrA. Therefore, in A. pasteurianus, UvrA could be induced by acetic acid and is related with the acetic acid tolerance by protecting the genome against acetic acid to ensure the protein expression and metabolism.

Microbial response to acid stress: mechanisms and applications

“…UvrABCD, DNA polymerase, and DNA ligase support the repair of acid-induced DNA damage, performing damage recognition, base excision, and gap filling (Das et al 2015). UvrA overexpression enhanced the acetic acid tolerance and fermentation of Acetobacter pasteurianus, which is a widely used vinegar-brewing acetic acid bacteria (Zheng et al 2018).…”

Fine‐tuning ethanol oxidation pathway enzymes and cofactor PQQ coordinates the conflict between fitness and acetic acid production by Acetobacter pasteurianus

“…pT‐aal, pT‐aal‐pqqAB and pT‐aal‐pqqABCDE) produced the highest acetic acid, with a yield of 41.21 ± 0.83, 41.75 ± 0.95 and 41.69 ± 0.82 g l ‐1 , respectively, in the presence of 1% initial acetic acid (Table S3). Their productivities (1.61 ± 0.07, 1.65 ± 0.09 and 1.67 ± 0.04 g l ‐1 h ‐1 ) were also significantly higher than from A. pasteurianus JST‐S/pBBR‐adhA‐adhB (Wu, et al ., 2017) and A. pasteurianus /pMV24‐ uvrA (Zheng, et al ., 2018), under the condition of shake flask with 1% initial acetic acid at 30° (Table 1). However, in the presence of 3% (v/v) initial acetic acid, acetic acid production of all engineered strains showed a significant drop compared to wild type (Fig.…”

“…In recent years, with in‐depth study of the acetic acid‐tolerance mechanisms of AAB, many genes and proteins related to stress response and tolerance, such as membrane‐bound ADH (Wu, et al ., 2017), nucleic acid repair enzyme UvrA (Zheng, et al ., 2018), aconitase (Nakano, et al ., 2004) and ABC transporter (Nakano, et al ., 2006), have been successfully identified, facilitating the application of genetic improvement to improve acetic acid tolerance and product yield. A comparative of acetic acid productivity in engineered A. pasteurianus and A. aceti strains, was summarized in Table 1.…”

Functional nano-catalyzed pyrolyzates from branch of Cinnamomum camphora

“…A1 and Table A1). A large amount of chemicals were detected in f. For example, Acetic acid (9.16%) is a good fixation fluid for fixed chromosomes (Zheng et al, 2018). Phenol, 2-methoxy- (3.21%) is used for the synthesis of dyes and is also an analytical reagent (Cheng et al, 2017).…”