scholarly journals A Multifunction ABC Transporter (Opt) Contributes to Diversity of Peptide Uptake Specificity within the Genus Lactococcus

2004 ◽  
Vol 186 (19) ◽  
pp. 6492-6500 ◽  
Author(s):  
Mauld Lamarque ◽  
Pascale Charbonnel ◽  
Dominique Aubel ◽  
Jean-Christophe Piard ◽  
Danièle Atlan ◽  
...  
Keyword(s):  
Sequence Analysis ◽  
Lactococcus Lactis ◽  
Abc Transporter ◽  
Binding Proteins ◽  
Wild Type ◽  
Genetic Organization ◽  
Peptide Uptake ◽  
Type Strains ◽  
Free Strains

ABSTRACT Growth of Lactococcus lactis in milk depends on the utilization of extracellular peptides. Up to now, oligopeptide uptake was thought to be due only to the ABC transporter Opp. Nevertheless, analysis of several Opp-deficient L. lactis strains revealed the implication of a second oligopeptide ABC transporter, the so-called Opt system. Both transporters are expressed in wild-type strains such as L. lactis SK11 and Wg2, whereas the plasmid-free strains MG1363 and IL-1403 synthesize only Opp and Opt, respectively. The Opt system displays significant differences from the lactococcal Opp system, which made Opt much more closely related to the oligopeptide transporters of streptococci than to the lactococcal Opp system: (i) genetic organization, (ii) peptide uptake specificity, and (iii) presence of two oligopeptide-binding proteins, OptS and OptA. The fact that only OptA is required for nutrition calls into question the function of the second oligopeptide binding protein (Opts). Sequence analysis of oligopeptide-binding proteins from different bacteria prompted us to propose a classification of these proteins in three distinct groups, differentiated by the presence (or not) of precisely located extensions.

An Origin of Transfer (oriT) on the Conjugative Element pRS01 from Lactococcus lactis subsp.lactis ML3

1998 ◽  
Vol 64 (4) ◽  
pp. 1541-1544 ◽  
Author(s):  
David A. Mills ◽  
Trevor G. Phister ◽  
Gary M. Dunny ◽  
Larry L. McKay
Keyword(s):  
Sequence Analysis ◽  
Lactococcus Lactis ◽  
Intergenic Region ◽  
Inverted Repeat ◽  
Previous Analysis ◽  
Open Reading Frames ◽  
Wild Type ◽  
Derivatives Of ◽  
Reading Frames ◽  
Origin Of Transfer

ABSTRACT Previous analysis of the Tra1 region of the conjugative element pRS01 from Lactococcus lactis subsp. lactis ML3 suggested that an origin of transfer (oriT) was present. Deletion derivatives of this cloned Tra1 region were assayed for mobilization in the presence of the wild-type pRS01 element intrans. The pRS01 oriT was localized to a 446-nucleotide segment in the intergenic region between open reading frames ltrD and ltrE. Sequence analysis of this region revealed a cluster of direct and inverted repeat structures characteristic of oriT regions associated with other conjugative systems.

Accumulation of casein-derived peptides during growth of proteinase-positive strains of Lactococcus lactis in milk: their contribution to subsequent bacterial growth is impaired by their internal transport

2000 ◽  
Vol 67 (2) ◽  
pp. 233-240 ◽  
Author(s):  
CATHERINE FOUCAUD ◽  
VINCENT JUILLARD
Keyword(s):  
Amino Acids ◽  
Lactococcus Lactis ◽  
Nutritional Value ◽  
Essential Amino Acids ◽  
Peptide Transport ◽  
Wild Type ◽  
Transport Mutants ◽  
Time Courses ◽  
Internal Transport ◽  
Type Strains

To explain the limited nutritional value of milk cultured with proteinase-positive (Prt+) strains of Lactococcus lactis for the subsequent growth of dairy lactococci, we investigated further the time courses of modifications in the free amino acid and peptide contents of cultured milk. When growing in milk for up to 24 h, Prt+ strains of Lc. lactis progressively accumulated amino acids and casein-derived peptides. The growth of proteinase-negative (Prt−) wild-type strains and peptide transport mutants of Lc. lactis in cultured milk showed that casein-derived peptides could sustain growth up to 5×108 cfu/ml, depending on the extent of casein degradation during the preliminary growth of Prt+ strains and the Prt− strains. Of the casein-derived oligopeptides, <25% were transported into the cell and used for Lc. lactis growth. However, they played a prominent role, contributing 90% to growth. In contrast, di- and tripeptides did not contribute to growth, suggesting that either few were released from caseins or they did not supply essential amino acids.

scholarly journals Whole-genome sequence analysis reveals unique SNP profiles to distinguish vaccine and wild-type strains of bovine herpesvirus-1 (BoHV-1)

Virology ◽  
2018 ◽  
Vol 522 ◽  
pp. 27-36 ◽  
Author(s):  
Shubhada K. Chothe ◽  
Aswathy Sebastian ◽  
Asha Thomas ◽  
Ruth H. Nissly ◽  
David Wolfgang ◽  
...  
Keyword(s):  
Sequence Analysis ◽  
Genome Sequence ◽  
Bovine Herpesvirus ◽  
Whole Genome Sequence ◽  
Whole Genome ◽  
Wild Type ◽  
Bovine Herpesvirus 1 ◽  
Genome Sequence Analysis ◽  
Herpesvirus 1 ◽  
Type Strains

scholarly journals A multilocus sequence analysis for the taxonomic update and identification of the genus Proteus

2020 ◽  
Author(s):  
Hang Dai ◽  
Binghuai Lu ◽  
Zhenpeng Li ◽  
Zhenzhou Huang ◽  
Hongyan Cai ◽  
...  
Keyword(s):  
Sequence Analysis ◽  
Phylogenetic Trees ◽  
Genetic Relationships ◽  
Housekeeping Genes ◽  
Multilocus Sequence Analysis ◽  
Gene Marker ◽  
Opportunistic Pathogens ◽  
Web Based ◽  
Type Strains

Abstract Background: The members of the genus Proteus are commonly opportunistic pathogens that cause a variety of infections in humans. The molecular evolutionary characteristics and genetic relationships among Proteus species are remain unelucidated. In this study, we developed a multilocus sequence analysis (MLSA) approach based on five housekeeping genes (HKGs) to delineate phylogenetic relationships of species within genus of Proteus. Results: Of all 223 Proteus strains collected in current study, phylogenetic tree of concatenated five HKGs (dnaJ, mdh, pyrC, recA and rpoD) divided into eleven clusters, which representative of their counterpart species. Meanwhile, phylogenetic trees of the five individual HKGs were also corresponded to that of the concatenated tree, except for recA, which clustered four strains at an independent cluster. The evaluation of inter- and intra-species distance of HKGs concatenation, all inter-species indicated more significant different distances than those of intra-species, which revealed these HKGs concatenation can be used as gene marker to distinguish different Proteus species. Further web-based DNA-DNA hybridization estimated by genome of type strains confirmed the validity of the MLSA and each of eleven clusters were congruent with eleven different Proteus species. In addition, we used the established MLSA method to identify the randomly collected Proteus, and found that P. mirabilis is the most species of Proteus. However, the top second is P. terrae, but not P. vulgaris. Combined with the genetic, genomic and phenotypic characteristics, three species, P. terrae, P. cibarius and Proteus genospecies 5 should be regarded as the heterotypic synonyms.Conclusions: Our data suggested the MLSA was a powerful method for the discrimination and classification of the Proteus at species level. The MLSA scheme provides a rapid, economical and precise identification of Proteus strains. The identification of Proteus species determined by the MLSA approach plays an important role in clinical diagnosis and treatment of Proteus infection.

scholarly journals Identification ofvib-1, a Locus Involved in Vegetative Incompatibility Mediated byhet-cinNeurospora crassa

Genetics ◽  
2002 ◽  
Vol 162 (1) ◽  
pp. 89-101 ◽  
Author(s):  
Qijun Xiang ◽  
N Louise Glass
Keyword(s):  
Acid Phosphatase ◽  
Recognition System ◽  
Deletion Mutants ◽  
Wild Type ◽  
Vegetative Incompatibility ◽  
Death Rates ◽  
Self Recognition ◽  
Allelic Differences ◽  
Native Gel ◽  
Type Strains

AbstractA non-self-recognition system called vegetative incompatibility is ubiquitous in filamentous fungi and is genetically regulated by het loci. Different fungal individuals are unable to form viable heterokaryons if they differ in allelic specificity at a het locus. To identify components of vegetative incompatibility mediated by allelic differences at the het-c locus of Neurospora crassa, we isolated mutants that suppressed phenotypic aspects of het-c vegetative incompatibility. Three deletion mutants were identified; the deletions overlapped each other in an ORF named vib-1 (vegetative incompatibility blocked). Mutations in vib-1 fully relieved growth inhibition and repression of conidiation conferred by het-c vegetative incompatibility and significantly reduced hyphal compartmentation and death rates. The vib-1 mutants displayed a profuse conidiation pattern, suggesting that VIB-1 is a regulator of conidiation. VIB-1 shares a region of similarity to PHOG, a possible phosphate nonrepressible acid phosphatase in Aspergillus nidulans. Native gel analysis of wild-type strains and vib-1 mutants indicated that vib-1 is not the structural gene for nonrepressible acid phosphatase, but rather may regulate nonrepressible acid phosphatase activity.

scholarly journals HET-E and HET-D Belong to a New Subfamily of WD40 Proteins Involved in Vegetative Incompatibility Specificity in the Fungus Podospora anserina

Genetics ◽  
2002 ◽  
Vol 161 (1) ◽  
pp. 71-81
Author(s):  
Eric Espagne ◽  
Pascale Balhadère ◽  
Marie-Louise Penin ◽  
Christian Barreau ◽  
Béatrice Turcq
Keyword(s):  
Genetic Difference ◽  
Podospora Anserina ◽  
Wild Type ◽  
Incompatible Interaction ◽  
Vegetative Incompatibility ◽  
Repeat Domain ◽  
Upper Face ◽  
E1a Gene ◽  
Type Strains ◽  
Wd40 Repeats

Abstract Vegetative incompatibility, which is very common in filamentous fungi, prevents a viable heterokaryotic cell from being formed by the fusion of filaments from two different wild-type strains. Such incompatibility is always the consequence of at least one genetic difference in specific genes (het genes). In Podospora anserina, alleles of the het-e and het-d loci control heterokaryon viability through genetic interactions with alleles of the unlinked het-c locus. The het-d2Y gene was isolated and shown to have strong similarity with the previously described het-e1A gene. Like the HET-E protein, the HET-D putative protein displayed a GTP-binding domain and seemed to require a minimal number of 11 WD40 repeats to be active in incompatibility. Apart from incompatibility specificity, no other function could be identified by disrupting the het-d gene. Sequence comparison of different het-e alleles suggested that het-e specificity is determined by the sequence of the WD40 repeat domain. In particular, the amino acids present on the upper face of the predicted β-propeller structure defined by this domain may confer the incompatible interaction specificity.

scholarly journals Extensive Phylogenetic Analysis of Piscine Orthoreovirus Genomic Sequences Shows the Robustness of Subgenotype Classification

Pathogens ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 41
Author(s):  
Marcos Godoy ◽  
Daniel A. Medina ◽  
Rudy Suarez ◽  
Sandro Valenzuela ◽  
Jaime Romero ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Genetic Variation ◽  
Sequence Analysis ◽  
Molecular Phylogeny ◽  
Phylogenetic Trees ◽  
Genomic Segment ◽  
Double Stranded Rna ◽  
The Family ◽  
Original Classification

Piscine orthoreovirus (PRV) belongs to the family Reoviridae and has been described mainly in association with salmonid infections. The genome of PRV consists of about 23,600 bp, with 10 segments of double-stranded RNA, classified as small (S1 to S4), medium (M1, M2 and M3) and large (L1, L2 and L3); these range approximately from 1000 bp (segment S4) to 4000 bp (segment L1). How the genetic variation among PRV strains affects the virulence for salmonids is still poorly understood. The aim of this study was to describe the molecular phylogeny of PRV based on an extensive sequence analysis of the S1 and M2 segments of PRV available in the GenBank database to date (May 2020). The analysis was extended to include new PRV sequences for S1 and M2 segments. In addition, subgenotype classifications were assigned to previously published unclassified sequences. It was concluded that the phylogenetic trees are consistent with the original classification using the PRV genomic segment S1, which differentiates PRV into two major genotypes, I and II, and each of these into two subgenotypes, designated as Ia and Ib, and IIa and IIb, respectively. Moreover, some clusters of country- and host-specific PRV subgenotypes were observed in the subset of sequences used. This work strengthens the subgenotype classification of PRV based on the S1 segment and can be used to enhance research on the virulence of PRV.

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