title: Biosynthesis of poly(3-hydroxybutyrateco-3-hydroxy-4-methylvalerate) by Strain Azotobacter chroococcum 7B.
abstract: Production of novel polyhydroxyalkanoates (PHAs), biodegradable polymers for biomedical applications, and biomaterials based on them is a promising trend in modern bioengineering. We studied the ability of an effective strain-producerAzotobacter chroococcum7B to synthesize not only poly(3-hydroxybutyrate) homopolymer (PHB) and its main copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), but also a novel copolymer, poly(3-hydroxybutyrate-co-3-hydroxy-4-methylvalerate) (PHB4MV). For the biosynthesis of PHB copolymers, we used carboxylic acids as additional carbon sources and monomer precursors in the chain of synthesized copolymers. The main parameters of these polymers' biosynthesis were determined: strain-producer biomass yield, polymer yield, molecular weight and monomer composition of the synthesized polymers, as well as the morphology ofA. chroococcum7B bacterial cells. The physico-chemical properties of the polymers were studied using nuclear magnetic resonance spectroscopy (NMR), differential scanning calorimetry (DSC), contact angle test, and other methods.In vitrobiocompatibility of the obtained polymers was investigated using stromal cells isolated from the bone marrow of rats with the XTT cell viability test. The synthesis of the novel copolymer PHB4MV and its chemical composition were demonstrated by NMR spectroscopy: the addition of 4-methylvaleric acid to the culture medium resulted in incorporation of 3-hydroxy-4-methylvalerate (3H4MV) monomers into the PHB polymer chain (0.6 mol%). Despite the low molar content of 3H4MV in the obtained copolymer, its physico-chemical properties were significantly different from those of the PHB homopolymer: it has lower crystallinity and a higher contact angle, i.e. the physico-chemical properties of the PHB4MV copolymer containing only 0.6 mol% of 3H4MV corresponded to a PHBV copolymer with a molar content ranging from 2.5% to 7.8%.In vitrobiocompatibility of the obtained PHB4MV copolymer, measured in the XTT test, was not statistically different from the cell growth of PHB and PHBV polymers, which make its use possible in biomedical research and development.
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia ; A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 33, bld. 2 Leninsky Ave., Moscow, 119071, Russia.
authors: A P
authors: AP
authors: Bonartsev
authors: A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 33, bld. 2 Leninsky Ave., Moscow, 119071, Russia.
authors: G A
authors: GA
authors: Bonartseva
authors: A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 33, bld. 2 Leninsky Ave., Moscow, 119071, Russia.
authors: V L
authors: VL
authors: Myshkina
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia.
authors: V V
authors: VV
authors: Voinova
authors: A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 33, bld. 2 Leninsky Ave., Moscow, 119071, Russia.
authors: T K
authors: TK
authors: Mahina
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia.
authors: I I
authors: II
authors: Zharkova
authors: A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 33, bld. 2 Leninsky Ave., Moscow, 119071, Russia.
authors: S G
authors: SG
authors: Yakovlev
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia.
authors: A L
authors: AL
authors: Zernov
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia.
authors: E V
authors: EV
authors: Ivanova
authors: A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 33, bld. 2 Leninsky Ave., Moscow, 119071, Russia.
authors: E A
authors: EA
authors: Akoulina
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia.
authors: E S
authors: ES
authors: Kuznetsova
authors: A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 33, bld. 2 Leninsky Ave., Moscow, 119071, Russia.
authors: V A
authors: VA
authors: Zhuikov
authors: JSC «Institute of Plastics», Petrovskiy proezd, 35, Moscow, 111024, Russia.
authors: S G
authors: SG
authors: Alekseeva
authors: Federal scientific-clinical center of physics-chemical medicine, Federal medical-biological agency, Malaya Pirogovskaya str., 1a, Moscow, 119435, Russia.
authors: V V
authors: VV
authors: Podgorskii
authors: Bauman Moscow State Technical University, 5, 2-nd Baumanskaya, Moscow, 105005, Russia.
authors: I V
authors: IV
authors: Bessonov
authors: Bauman Moscow State Technical University, 5, 2-nd Baumanskaya, Moscow, 105005, Russia.
authors: M N
authors: MN
authors: Kopitsyna
authors: Bauman Moscow State Technical University, 5, 2-nd Baumanskaya, Moscow, 105005, Russia.
authors: A S
authors: AS
authors: Morozov
authors: Faculty of Soil Science, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234, Russia.
authors: E Y
authors: EY
authors: Milanovskiy
authors: Faculty of Soil Science, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234, Russia.
authors: Z N
authors: ZN
authors: Tyugay
authors: Faculty of Soil Science, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234, Russia.
authors: G S
authors: GS
authors: Bykova
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia.
authors: M P
authors: MP
authors: Kirpichnikov
authors: Faculty of Biology, M.V.Lomonosov Moscow State University, Leninskie gory, 1-12, Moscow, 119234 , Russia.
authors: K V
authors: KV
authors: Shaitan
keywords: Azotobacter chroococcum 7B; biocompatibility; biosynthesis; bone marrow stromal cells; crystallinity; poly(3-hydroxybutyrate); poly(3-hydroxybutyrate-co-3-hydroxy-4-methylvalerate)