Morphological and molecular identification of a new halotolerant cyanobacterial strain, Limnospira fusiformis TL03, isolated from Telamine Lake in the northwest of Algeria

Abstract

This study examines a new strain, Limnospira fusiformis TL03, isolated from Lake Telamine in northwest Algeria. The strain was morphologically identified using a light microscope and molecularly characterized using its 16S rRNA gene sequence. The effect of salinity on growth and photosynthetic pigments was studied using a spectrophotometric method; different sodium chloride concentrations (0, 5, 15, 30, 45, and 60 g/l) in blue-green medium (BG11) cultured uniformly as homogenized cell suspension were tested. A morphological examination confirmed that the isolated strain belonged to the Limnospira genus. It has trichome lengths ranging from 210-2027 µm, as well as pitch and coil diameters ranging from 30-137 µm and 20-60 µm, respectively. The data from the 16S rRNA gene sequence analysis confirmed that the isolated strain was Limnospira fusiformis TL03 with 100% sequence similarity to Limnospira fusiformis SAG 85.79. The results also indicate that this strain can grow at various salt concentrations, with the highest optical density values (1.58 ± 0.014 and 1.56 ± 0.003) obtained in cultures containing 15 g/L and 5 g/L NaCl, respectively.