title: Involvement of the ornithine decarboxylase gene in acid stress response in probiotic Lactobacillus delbrueckii UFV H2b20.
abstract: Amino acid decarboxylation is important for the maintenance of intracellular pH under acid stress. This study aims to carry out phylogenetic and expression analysis by real-time PCR of two genes that encode proteins involved in ornithine decarboxylation in Lactobacillus delbrueckii UFV H2b20 exposed to acid stress. Sequencing and phylogeny analysis of genes encoding ornithine decarboxylase and amino acid permease in L. delbrueckii UFV H2b20 showed their high sequence identity (99%) and grouping with those of L. delbrueckii subsp. bulgaricus ATCC 11842. Exposure of L. delbrueckii UFV H2b20 cells in MRS pH 3.5 for 30 and 60 min caused a significant increase in expression of the gene encoding ornithine decarboxylase (up to 8.1 times higher when compared to the control treatment). Increased expression of the ornithine decarboxylase gene demonstrates its involvement in acid stress response in L. delbrueckii UFV H2b20, evidencing that the protein encoded by that gene could be involved in intracellular pH regulation. The results obtained show ornithine decarboxylation as a possible mechanism of adaptation to an acidic environmental condition, a desirable and necessary characteristic for probiotic cultures and certainly important to the survival and persistence of the L. delbrueckii UFV H2b20 in the human gastrointestinal tract.
authors: 1 Universidade Federal de Viçosa, Instituto de Biotecnologia Aplicada à Agropecuária-BIOAGRO, Departamento de Microbiologia, Viçosa, MG 36571-000, Brazil.
authors: A B
authors: AB
authors: Ferreira
authors: 2 Universidade Federal de Juiz de Fora, Departamento Básico - Área Saúde, Governador Valadares, MG 35020-220, Brazil.
authors: M N V de
authors: MN
authors: Oliveira
authors: 1 Universidade Federal de Viçosa, Instituto de Biotecnologia Aplicada à Agropecuária-BIOAGRO, Departamento de Microbiologia, Viçosa, MG 36571-000, Brazil.
authors: F S
authors: FS
authors: Freitas
authors: 3 Universidade Federal de Juiz de Fora, Departamento de Imunologia, Microbiologia e Parasitologia. Juiz de Fora, MG 36036-330, Brazil.
authors: A D
authors: AD
authors: Paiva
authors: 1 Universidade Federal de Viçosa, Instituto de Biotecnologia Aplicada à Agropecuária-BIOAGRO, Departamento de Microbiologia, Viçosa, MG 36571-000, Brazil.
authors: P
authors: P
authors: Alfenas-Zerbini
authors: 4 Universidade Federal dos Vales do Jequitinhonha e Mucuri, Departamento de Nutrição, Diamantina, MG 39100-000, Brazil.
authors: D F da
authors: DF
authors: Silva
authors: 1 Universidade Federal de Viçosa, Instituto de Biotecnologia Aplicada à Agropecuária-BIOAGRO, Departamento de Microbiologia, Viçosa, MG 36571-000, Brazil.
authors: M V de
authors: MV
authors: Queiroz
authors: 1 Universidade Federal de Viçosa, Instituto de Biotecnologia Aplicada à Agropecuária-BIOAGRO, Departamento de Microbiologia, Viçosa, MG 36571-000, Brazil.
authors: A C
authors: AC
authors: Borges
authors: 1 Universidade Federal de Viçosa, Instituto de Biotecnologia Aplicada à Agropecuária-BIOAGRO, Departamento de Microbiologia, Viçosa, MG 36571-000, Brazil.
authors: C A de
authors: CA
authors: Moraes
mesh_terms: D000143:Acids / Q000633:toxicity*; D026905:Amino Acid Transport Systems / Q000235:genetics / Q000378:metabolism; D016000:Cluster Analysis; D020869:Gene Expression Profiling; D006801:Humans; D048668:Lactobacillus delbrueckii / Q000187:drug effects* / Q000201:enzymology* / Q000502:physiology; D009955:Ornithine Decarboxylase / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013312:Stress, Physiological
chemical_list: D000143:Acids; D026905:Amino Acid Transport Systems; D009955:Ornithine Decarboxylase
keywords: amino acid decarboxylation; molecular phylogeny; real-time PCR