scholarly journals Examination of antimicrobial potential in natural isolates of lactobacillus casei/paracasei group

Genetika ◽  
2012 ◽  
Vol 44 (3) ◽  
pp. 661-677 ◽  
Author(s):  
Maja Tolinacki ◽  
Jelena Lozo ◽  
Katarina Veljovic ◽  
Milan Kojic ◽  
Djordje Fira ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Abc Transporter ◽  
Lactobacillus Casei ◽  
Bacteriocin Production ◽  
Accessory Protein ◽  
Terminal Sequence ◽  
Antimicrobial Potential ◽  
Genes Encoding ◽  
Natural Isolates ◽  
Production Strain

The aim of this study was to investigate the antimicrobial potential of 52 natural isolates of Lactobacillus casei/paracasei. The incidence of relevant genes encoding BacSJ (bacSJ2-8/bacSJ2-8i gene cluster), acidocin 8912 (acdT), ABC-transporter (abcT) and accessory protein (acc) was also studied. These genes were found to be widespread amongst the analyzed L. casei/paracasei strains. The bacSJ2-8/bacSJ2-8i gene cluster was present in 49 (94.23%) and acdT in 41 (78.85%) of the 52 tested strains. Forty of these strains (76.92%) harbored both analyzed genes. Interestingly, only 17 strains (32.69%) with the bacSJ2-8/bacSJ2-8i gene cluster and/or the acdT gene showed bacteriocin production. Strain L. paracasei BGNK1-62 contained the bacSJ2-8/bacSJ2-8i gene cluster, but did not produce bacteriocin BacSJ possibly due to absence of the abcT and acc genes. Hence, these genes were introduced into BGNK1-62 by transformation with constructed plasmid pA2A, after which BacSJ was produced. In addition, it was found that L. paracasei BGGR2-66 produced new bacteriocin designated as BacGR that was biochemically characterized and its N- terminal sequence was determined.

scholarly journals Malic Enzyme and Malolactic Enzyme Pathways Are Functionally Linked but Independently Regulated in Lactobacillus casei BL23

2013 ◽  
Vol 79 (18) ◽  
pp. 5509-5518 ◽  
Author(s):  
José María Landete ◽  
Sergi Ferrer ◽  
Vicente Monedero ◽  
Manuel Zúñiga
Keyword(s):  
Carbon Source ◽  
Gene Cluster ◽  
Malic Enzyme ◽  
Lactobacillus Casei ◽  
Growth Defect ◽  
Two Component System ◽  
Content Type ◽  
Malolactic Enzyme ◽  
Genes Encoding ◽  
Malate Metabolism

ABSTRACTLactobacillus caseiis the only lactic acid bacterium in which two pathways forl-malate degradation have been described: the malolactic enzyme (MLE) and the malic enzyme (ME) pathways. Whereas the ME pathway enablesL. caseito grow onl-malate, MLE does not support growth. Themlegene cluster consists of three genes encoding MLE (mleS), the putativel-malate transporter MleT, and the putative regulator MleR. Themaegene cluster consists of four genes encoding ME (maeE), the putative transporter MaeP, and the two-component system MaeKR. Since both pathways compete for the same substrate, we sought to determine whether they are coordinately regulated and their role inl-malate utilization as a carbon source. Transcriptional analyses revealed that themleandmaegenes are independently regulated and showed that MleR acts as an activator and requires internalization ofl-malate to induce the expression ofmlegenes. Notwithstanding, bothl-malate transporters were required for maximall-malate uptake, although only anmleTmutation caused a growth defect onl-malate, indicating its crucial role inl-malate metabolism. However, inactivation of MLE resulted in higher growth rates and higher final optical densities onl-malate. The limited growth onl-malate of the wild-type strain was correlated to a rapid degradation of the availablel-malate tol-lactate, which cannot be further metabolized. Taken together, our results indicate thatL. caseil-malate metabolism is not optimized for utilization ofl-malate as a carbon source but for deacidification of the medium by conversion ofl-malate intol-lactate via MLE.

scholarly journals Characterization of a Novel Glucosamine-6-Phosphate Deaminase from a Hyperthermophilic Archaeon

2005 ◽  
Vol 187 (20) ◽  
pp. 7038-7044 ◽  
Author(s):  
Takeshi Tanaka ◽  
Fumikazu Takahashi ◽  
Toshiaki Fukui ◽  
Shinsuke Fujiwara ◽  
Haruyuki Atomi ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Abc Transporter ◽  
Catalytic Properties ◽  
Sugar Metabolism ◽  
Amino Sugar ◽  
Hyperthermophilic Archaeon ◽  
Chitin Degradation ◽  
Genes Encoding ◽  
Activity Dependent

ABSTRACT A key step in amino sugar metabolism is the interconversion between fructose-6-phosphate (Fru6P) and glucosamine-6-phosphate (GlcN6P). This conversion is catalyzed in the catabolic and anabolic directions by GlcN6P deaminase and GlcN6P synthase, respectively, two enzymes that show no relationship with one another in terms of primary structure. In this study, we examined the catalytic properties and regulatory features of the glmD gene product (GlmD Tk ) present within a chitin degradation gene cluster in the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1. Although the protein GlmD Tk was predicted as a probable sugar isomerase related to the C-terminal sugar isomerase domain of GlcN6P synthase, the recombinant GlmD Tk clearly exhibited GlcN6P deaminase activity, generating Fru6P and ammonia from GlcN6P. This enzyme also catalyzed the reverse reaction, the ammonia-dependent amination/isomerization of Fru6P to GlcN6P, whereas no GlcN6P synthase activity dependent on glutamine was observed. Kinetic analyses clarified the preference of this enzyme for the deaminase reaction rather than the reverse one, consistent with the catabolic function of GlmD Tk . In T. kodakaraensis cells, glmDTk was polycistronically transcribed together with upstream genes encoding an ABC transporter and a downstream exo-β-glucosaminidase gene (glmATk ) within the gene cluster, and their expression was induced by the chitin degradation intermediate, diacetylchitobiose. The results presented here indicate that GlmD Tk is actually a GlcN6P deaminase functioning in the entry of chitin-derived monosaccharides to glycolysis in this hyperthermophile. This enzyme is the first example of an archaeal GlcN6P deaminase and is a structurally novel type distinct from any previously known GlcN6P deaminase.

scholarly journals Identification of genes encoding a novel ABC transporter in Lactobacillus delbrueckii for inulin polymers uptake

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuji Tsujikawa ◽  
Shu Ishikawa ◽  
Iwao Sakane ◽  
Ken-ichi Yoshida ◽  
Ro Osawa
Keyword(s):  
Bacillus Subtilis ◽  
Carbon Source ◽  
Heterologous Expression ◽  
Gene Cluster ◽  
Abc Transporter ◽  
Transcriptome Analysis ◽  
Sole Carbon Source ◽  
Cultured Cells ◽  
Lactobacillus Delbrueckii ◽  
Genes Encoding

AbstractLactobacillus delbrueckii JCM 1002T grows on highly polymerized inulin-type fructans as its sole carbon source. When it was grown on inulin, a > 10 kb long gene cluster inuABCDEF (Ldb1381-1386) encoding a plausible ABC transporter was suggested to be induced, since a transcriptome analysis revealed that the fourth gene inuD (Ldb1384) was up-regulated most prominently. Although Bacillus subtilis 168 is originally unable to utilize inulin, it became to grow on inulin upon heterologous expression of inuABCDEF. When freshly cultured cells of the recombinant B. subtilis were then densely suspended in buffer containing inulin polymers and incubated, inulin gradually disappeared from the buffer and accumulated in the cells without being degraded, whereas levan-type fructans did not disappear. The results imply that inuABCDEF might encode a novel ABC transporter in L. delbrueckii to “monopolize” inulin polymers selectively, thereby, providing a possible advantage in competition with other concomitant inulin-utilizing bacteria.

scholarly journals Genetic Investigation of the Catabolic Pathway for Degradation of Abietane Diterpenoids by Pseudomonas abietaniphilaBKME-9

2000 ◽  
Vol 182 (13) ◽  
pp. 3784-3793 ◽  
Author(s):  
Vincent J. J. Martin ◽  
William W. Mohn
Keyword(s):  
Gene Cluster ◽  
Sequence Similarity ◽  
Open Reading Frames ◽  
Ring Cleavage ◽  
Catabolic Pathway ◽  
Transcriptional Fusion ◽  
Abietane Diterpenoids ◽  
Genes Encoding ◽  
Dna Fragment ◽  
Reading Frames

ABSTRACT We have cloned and sequenced the dit gene cluster encoding enzymes of the catabolic pathway for abietane diterpenoid degradation by Pseudomonas abietaniphila BKME-9. Thedit gene cluster is located on a 16.7-kb DNA fragment containing 13 complete open reading frames (ORFs) and 1 partial ORF. The genes ditA1A2A3 encode the α and β subunits and the ferredoxin of the dioxygenase which hydroxylates 7-oxodehydroabietic acid to 7-oxo-11,12-dihydroxy-8,13-abietadien acid. The dioxygenase mutant strain BKME-941 (ditA1::Tn5) did not grow on nonaromatic abietanes, and transformed palustric and abietic acids to 7-oxodehydroabietic acid in cell suspension assays. Thus, nonaromatic abietanes are aromatized prior to further degradation. Catechol 2,3-dioxygenase activity of xylEtranscriptional fusion strains showed induction of ditA1and ditA3 by abietic, dehydroabietic, and 7-oxodehydroabietic acids, which support the growth of strain BKME-9, as well as by isopimaric and 12,14-dichlorodehydroabietic acids, which are diterpenoids that do not support the growth of strain BKME-9. In addition to the aromatic-ring-hydroxylating dioxygenase genes, thedit cluster includes ditC, encoding an extradiol ring cleavage dioxygenase, and ditR, encoding an IclR-type transcriptional regulator. Although ditR is not strictly required for the growth of strain BKME-9 on abietanes, aditR::Kmr mutation in aditA3::xylE reporter strain demonstrated that it encodes an inducer-dependent transcriptional activator of ditA3. An ORF with sequence similarity to genes encoding permeases (ditE) is linked with genes involved in abietane degradation.

scholarly journals Spontaneous Amplification of the Actinorhodin Gene Cluster in Streptomyces coelicolor Involving Native Insertion Sequence IS466

2008 ◽  
Vol 190 (13) ◽  
pp. 4754-4758 ◽  
Author(s):  
E. M. Widenbrant ◽  
Hsiu-Hui Tsai ◽  
Carton W. Chen ◽  
C. M. Kao
Keyword(s):  
Transposable Element ◽  
Gene Cluster ◽  
Insertion Sequence ◽  
Streptomyces Coelicolor ◽  
Biosynthetic Enzymes ◽  
Genes Encoding ◽  
Amplification Mechanism

ABSTRACT We observed a spontaneous amplification of the Streptomyces coelicolor chromosome, including genes encoding biosynthetic enzymes of the antibiotic actinorhodin. A new junction of two tandem segments has, inserted within it, a third copy of a transposable element existing in two places elsewhere in the chromosome, suggesting its involvement in the amplification mechanism.

scholarly journals Characterization of a novel 3-O-α-D-galactosyl-α-L-arabinofuranosidase for the assimilation of gum arabic AGP in Bifidobacterium longum subsp. longum

2021 ◽  
Author(s):  
Yuki Sasaki ◽  
Ayako Horigome ◽  
Toshitaka Odamaki ◽  
Jin-Zhong Xiao ◽  
Akihiro Ishiwata ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Bifidobacterium Longum ◽  
Gum Arabic ◽  
Glycoside Hydrolase Family ◽  
Type Ii ◽  
Cooperative Action ◽  
Genes Encoding ◽  
Key Enzyme ◽  
Degradative Enzymes

Gum arabic arabinogalactan (AG) protein (AGP) is a unique dietary fiber that is degraded and assimilated by only specific strains of Bifidobacterium longum subsp. longum. Here, we identified a novel 3-O-α-d-galactosyl-α-l-arabinofuranosidase (GAfase) from B. longum JCM7052, and classified it into the glycoside hydrolase family 39 (GH39). GAfase released α-d-Galp-(1→3)-l-Ara and β-l-Arap-(1→3)-l-Ara from gum arabic AGP and β-l-Arap-(1→3)-l-Ara from larch AGP, and the α-d-Galp-(1→3)-l-Ara release activity was found to be 594-fold higher than that of β-l-Arap-(1→3)-l-Ara. The GAfase gene was part of a gene cluster that included genes encoding a GH36 α-galactosidase candidate and ABC transporters for the assimilation of the released α-d-Galp-(1→3)-l-Ara in B. longum. Notably, when α-d-Galp-(1→3)-l-Ara was removed from gum arabic AGP, it was assimilated by both B. longum JCM7052 and the non-assimilative B. longum JCM1217, suggesting that the removal of α-d-Galp-(1→3)-l-Ara from gum arabic AGP by GAfase permitted the cooperative action with type-II AG degradative enzymes in B. longum. The present study provides new insight into the mechanism of gum arabic AGP degradation in B. longum. IMPORTANCE Bifidobacteria harbor numerous carbohydrate-active enzymes that degrade several dietary fibers in the gastrointestinal tract. B. longum JCM7052 is known to exhibit the ability to assimilate gum arabic AGP, but the key enzyme involved in the degradation of gum arabic AGP remains unidentified. Here, we cloned and characterized a GH39 3-O-α-d-galactosyl-α-l-arabinofuranosidase (GAfase) from B. longum JCM7052. The enzyme was responsible for the release of α-d-Galp-(1→3)-l-Ara and β-l-Arap-(1→3)-l-Ara from gum arabic AGP. The presence of a gene cluster including the GAfase gene is specifically observed in gum arabic AGP assimilative strains. However, GAfase-carrier strains may affect GAfase-noncarrier strains that express other type-II AG degradative enzymes. These findings provide insights into the bifidogenic effect of gum arabic AGP.

Characterization of the cysK2-ctl1-cysE2 gene cluster involved in sulfur metabolism in Lactobacillus casei

2012 ◽  
Vol 152 (3) ◽  
pp. 211-219 ◽  
Author(s):  
Biljana Bogicevic ◽  
Stefan Irmler ◽  
Reto Portmann ◽  
Leo Meile ◽  
Hélène Berthoud
Keyword(s):  
Gene Cluster ◽  
Lactobacillus Casei ◽  
Sulfur Metabolism

scholarly journals Cloning, Sequencing, and Characterization of a Gene Cluster Involved in EDTA Degradation from the Bacterium BNC1

2001 ◽  
Vol 67 (2) ◽  
pp. 688-695 ◽  
Author(s):  
Jan Bohuslavek ◽  
Jason W. Payne ◽  
Yong Liu ◽  
Harvey Bolton ◽  
Luying Xun
Keyword(s):  
Gene Cluster ◽  
Genomic Library ◽  
Regulatory Protein ◽  
Chelating Agent ◽  
Environmental Pollutant ◽  
Flavin Mononucleotide ◽  
Bacterial Strains ◽  
System A ◽  
Monooxygenase Gene ◽  
Genes Encoding

ABSTRACT EDTA is a chelating agent, widely used in many industries. Because of its ability to mobilize heavy metals and radionuclides, it can be an environmental pollutant. The EDTA monooxygenases that initiate EDTA degradation have been purified and characterized in bacterial strains BNC1 and DSM 9103. However, the genes encoding the enzymes have not been reported. The EDTA monooxygenase gene was cloned by probing a genomic library of strain BNC1 with a probe generated from the N-terminal amino acid sequence of the monooxygenase. Sequencing of the cloned DNA fragment revealed a gene cluster containing eight genes. Two of the genes, emoA and emoB, were expressed inEscherichia coli, and the gene products, EmoA and EmoB, were purified and characterized. Both experimental data and sequence analysis showed that EmoA is a reduced flavin mononucleotide-utilizing monooxygenase and that EmoB is an NADH:flavin mononucleotide oxidoreductase. The two-enzyme system oxidized EDTA to ethylenediaminediacetate (EDDA) and nitrilotriacetate (NTA) to iminodiacetate (IDA) with the production of glyoxylate. TheemoA and emoB genes were cotranscribed when BNC1 cells were grown on EDTA. Other genes in the cluster encoded a hypothetical transport system, a putative regulatory protein, and IDA oxidase that oxidizes IDA and EDDA. We concluded that this gene cluster is responsible for the initial steps of EDTA and NTA degradation.

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