Content of vitamins in Halobacterium halobium 353П ВКПМ В - 1739 and effect of its “purple membrane”- free lysate onto colony growth of bacteria

Abstract

Cells of Halobacterium halobium strain 353П ВКПМ В-1739 were tested for content of vitamins А, β-carotene, D, E, K, C, B1, B2, B3, B5, B6, Bc, B12, H and РР. Cell suspension of 109 cells/ml was prepared in isotonic NaCl solution with use of an optical standard. To obtain probes for analyses, equal volumes of the suspension were centrifuged and cell pellets were subjected to lysis in distilled water. The vitamin content was not significant, as bacterium produced them according to its own requirements. Particularly, we determined the vitamins, μg/L: retinaldehyde – 38.4 ± 0.3; β-carotene – 74.6 ± 0.5; α- tocopherol – 16.8 ± 0.4; thiamine – 38.2 ± 0.1; riboflavin – 53.5 ± 0.4; vitamin В5 – 49.7 ± 0.3; pyridoxine – 10.0 ± 0.1; cyanocobalamin – 8.1 ± 0.2; folic acid – 18.6 ± 0.3; biotin – 2.9 ± 0.2; nicotinic acid – 172.1 ± 0.4. The strain is producing vitamins А, Е, B1, Вс and РР, the commercial microbiological production of which does not yet exist. The strain has prospects for biotechnological improvement as a producer of these compounds or as a donor of genes for their synthesis. When “purple membrane”- free lysate of H. halobium strain 353П ВКПМ В-1739 was added in proportion 1:1 to the water used for the nutritive media preparation, it stimulated the colony growth of Escherichia coli, Shigella sp., Klebsiella pneumoniae, Erwinia sp. and Pseudomonas sp. by 11-200, 50-60, 29-125, 60-130 and 95-106%, respectively. The highest enhancement of colony growth, around 350%, was observed for H. halobium 353 П ВКПМ В -1739. The “purple membrane”- free lysate was lyophilized. This allowed us to estimate the lysate dry matter content as 1.5%. In this state it was stored at 4°C for 6 months of observation without loss of its effect on bacterial growth. Thus, it can be used as a growth stimulator in microbiological media. Key words: Halobacterium halobium vitamins, “purple membrane”- free lysate, bacteria from different ecological groups, colony growth stimulation