Genome Features and Biochemical Characteristics of a Robust, Fast Growing and Naturally Transformable Cyanobacterium Synechococcus elongatus PCC 11801 Isolated from India.

ABSTRACT

Cyanobacteria provide an interesting platform for biotechnological applications due to their efficient photoautotrophic growth, amenability to genetic engineering and the ability to grow on non-arable land. An ideal industrial strain of cyanobacteria would need to be fast growing and tolerant to high levels of temperature, light, carbon dioxide, salt and be naturally transformable. In this study, we report Synechococcus elongatus PCC 11801, a strain isolated from India that fulfills these requirements. The physiological and biochemical characteristics of PCC 11801 under carbon and light-limiting conditions were investigated. PCC 11801 shows a doubling time of 2.3 h, that is the fastest growth for any cyanobacteria reported so far under ambient CO2 conditions. Genome sequence of PCC 11801 shows genome identity of ~83% with its closest neighbors Synechococcus elongatus PCC 7942 and Synechococcus elongatus UTEX 2973. The unique attributes of PCC 11801 genome are discussed in light of the physiological characteristics that are needed in an industrial strain. The genome of PCC 11801 shows several genes that do not have homologs in neighbor strains PCC 7942 and UTEX 2973, some of which may be responsible for adaptation to various abiotic stresses. The remarkably fast growth rate of PCC 11801 coupled with its robustness and ease of genetic transformation makes it an ideal candidate for the photosynthetic production of fuels and chemicals.