microorganisms Article A Blue-Purple Pigment-Producing Bacterium Isolated from the Vezelka River in the City of Belgorod Nikita S. Lyakhovchenko 1 , Tatiana N. Abashina 2 , Valentina N. Polivtseva 2 , Vladislav Yu. Senchenkov 1 , Daniil A. Pribylov 1 , Anna A. Chepurina 1 , Ilja A. Nikishin 1 , Alina A. Avakova 1 , Michael A. Goyanov 1 , Elizaveta D. Gubina 1 , Daria A. Churikova 1 , Alexander A. Sirotin 1 , Nataliya E. Suzina 2 and Inna P. Solyanikova 1,2, *   Citation: Lyakhovchenko, N.S.; Abashina, T.N.; Polivtseva, V.N.; Senchenkov, V.Y.; Pribylov, D.A.; Chepurina, A.A.; Nikishin, I.A.; Avakova, A.A.; Goyanov, M.A.; Gubina, E.D.; et al. A Blue-Purple Pigment-Producing Bacterium Isolated from the Vezelka River in the City of Belgorod. Microorganisms 2021, 9, 102. https://doi.org/10.3390/ microorganisms9010102 Received: 26 November 2020 Accepted: 30 December 2020 Published: 5 January 2021 Publisher’s Note: MDPI stays neu- tral with regard to jurisdictional clai- ms in published maps and institutio- nal affiliations. Copyright: © 2021 by the authors. Li- censee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and con- ditions of the Creative Commons At- tribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Federal State Autonomous Educational Institution of Higher Education, Belgorod National Research University, 308015 Belgorod, Russia; nikitkibullmail@gmail.com (N.S.L.); vladiksenchencov@gmail.com (V.Y.S.); daniil.pribylov@yandex.ru (D.A.P.); post0765@yandex.ru (A.A.C.); ilaynikishin@gmail.com (I.A.N.); avakova1200@gmail.com (A.A.A.);666mihai999@gmail.com (M.A.G.); dml1xngubina@yandex.ru (E.D.G.); daria.tchurikova@yandex.ru (D.A.C.); sirotin19402702@mail.ru (A.A.S.) 2 G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino Center for Biological Research of the Russian Academy of Sciences, Pushchino, 142290 Moscow, Russia; tanica@rambler.ru (T.N.A.); kaistia@gmail.com (V.N.P.); suzina_nataliya@rambler.ru (N.E.S.) * Correspondence: innas@ibpm.pushchino.ru Abstract: Violacein is a biotechnologically significant secondary metabolite due to its antibacterial, antifungal, and other properties. Isolation, research, and identification of violacein producing strains are of interest for the development of biotechnological processes, in order to enhance the biosynthesis of this compound. The purpose of the present work was to study the properties of a newly isolated bacterium capable of synthesizing blue-purple pigment. An aboriginal bacterium was isolated from the coastal zone of the Vezelka River in the city of Belgorod. Based on chemical and spectrophotometric studies of the crude ethanol extract, the pigment was identified as violacein, and the isolate was assigned to the group of violacein-forming bacteria, which includes bacteria of the genera Chromobacterium, Iodobacter, Janthinobacterium, Duganella, Collimonas, and Massilia. Based on cultural, morphological, tinctorial, physiological, and biochemical properties, as well as analysis of the 16S rRNA gene sequence, the new isolated strain was assigned to the genus Janthinobacterium. The isolated strain is capable of suppressing the growth of a number of fungal and bacterial phytopathogens. For representatives of the genus Janthinobacterium, their inhibitory influence on cyanobacteria was shown for the first time. Keywords: Janthinobacterium sp., identification; violacein; biotechnological significance 1. Introduction Bacterial cells produce a huge number of biologically active compounds, including vitamins, amino acids, antibiotics, and enzymes [1]. At present, the biotechnological significance of one more group of secondary metabolites of bacteria, pigments, has been estimated [2]. The ability to synthesize pigments that differ in chemical composition, color, and solubility is characteristic of many microorganisms [3]. The role of pigments for microorganisms may be to participate in respiration processes, to protect against ultraviolet radiation. In addition, some microorganisms synthesize pig- ments that have antibacterial and/or antifungal properties. The formation of secondary metabolites by microorganisms, providing their antagonistic effects, is an adaptation to the conditions of existence in the microbial community along with other forms of interaction both within the consortium and for other systems associated with it. The phenomenon of antagonism among microorganisms is widely used in medicine and agriculture. Live antagonist microbes are used in medical practice to combat dysbacteriosis and candidomy- cosis, which sometimes occur with the use of broad-spectrum antibiotics, for therapy and Microorganisms 2021, 9, 102. https://doi.org/10.3390/microorganisms9010102 https://www.mdpi.com/journal/microorganisms