When a phage infection did occur, the standard practice was to eliminate all of the contaminated material, followed by cleaning and sterilization. The infected broth in tons will be drafted in an industrial case which led to the direct cost loss and environmental problems. Hence, Pitavastatin price to

seek an economic treatment procedure or remedial method is a definite interest for industrial plants. 2-keto-d-gluconic acid (2KGA) is a key organic acid due to its intermediate role in the manufacture of erythorbic acid, an antioxidant widely used in food industry [6]. It is produced in an industrial scale by various bacteria including Cluconobacter oxydans Pseudogluconobacter Pseudogluconobacter saccharoketogenes, and Pseudomonas sorbosoxida[6–9]. Similarly, bacteriophages attack and lyse the 2KGA producing bacteria to lower substrate consumption or end-product yield and even stop the fermentation process. For example, a serious bacteriophage infection of 2KGA fermentation occurred widely in most Chinese plants in spring of 1999 [9]. Five bacteriophages (KS502, KS503, KS211, KS212 and KS213) had been isolated from the abnormal Pseudomonas fluorescens K1005 and Arthrobacter Ruboxistaurin order globiformis K1022 cultured broth [10, 11].

The new immunized strains including P. fluorescens AR3, AR4, AR12 and AR16 were generated to counter the phage contamination [12]. However, the repercussions caused by the phage infections still reoccurred in majority of Chinese 2KGA producing factories. Thus, besides scrupulous hygiene and screening immunised strains, the characteristic knowledge of bacterial phages and the economical remedial treatments were still needed for 2KGA industrial factories. This present study will focus on: 1) isolating and characterizing of a novel phage specifically infecting Pseudomonas fluorescens K1005 in the abnormal 2KGA industrial fermentation, and 2) proposing an effective and economical remedial action Alanine-glyoxylate transaminase to complete the production process with high

2KGA fermentation performance. Results and discussion Isolation and morphology of bacteriophage KSL-1 Abnormal fermentation broth samples from a 2KGA production plant were used to detect the presence of phages against the indicator strain of Ps. fluorescens K1005. Only one type of phage was isolated, purified and designated as KSL-1. It showed the lytic activity and high specificity towards its host bacteria Pseudomonas fluorescens K1005. Other tested Pseudomonas fluorescens strains of A46 and AR4 could not be infected by the phage KSL-1. The phage KSL-1 formed small, round plaques (about 1.0 mm in diameter) with transparent middle and turbid edge slightly on the double-layer plate (Figure 1a). The electron micrographs (Figure 1b and c) showed that KSL-1 has a hexagonal head diameter of about 99 nm and a non-contractile tail of about 103 nm × 39 nm. According to the International Committee on Taxonomy of Viruses, the phage KSL-1 belonged to family Siphoviridae [13, 14].