Restriction mapping and localization of the lactose-metabolizing genes of Streptococcus cremoris pDI-21

Yu, Pak-Lam; Appleby, Ruth D.; Pritchard, G. G.; Limsowtin, G. K. Y.

doi:10.1007/bf00255999

Cited by 10 publications

(4 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The other end of the operon included the 4.3-kbp XhoI fragment, since this fragment encodes the phospho-,-galactosidase gene of the operon (27). The large size of the pSK11L lactose operon is in accordance with previously characterized lactococcal lactose operons which have been shown to contain not only the three genes of the lactose phosphoenolpyruvate phosphotransferase system but also the tagatose-6-phosphate pathway genes and an open reading frame (ORF) with an undetermined function (35). pSK11L contained two lactococcal insertion elements.…”

Section: Resultssupporting

confidence: 84%

“…ISSJ has previously been shown to mediate cointegration with conjugal plasmids or chromosomal conjugal elements in other lactococcal strains (2, 12). Yu et al (35) reported isolation of a lactose plasmid (pDI-21) from L. cremoris H2 by conjugal transfer to a plasmid-free L. lactis strain. Interestingly, the order and distribution of restriction sites in pDI-21 are very similar to those of the restriction sites in pSK11L up to the region that contains ISSJ.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Replication and temperature-sensitive maintenance functions of lactose plasmid pSK11L from Lactococcus lactis subsp. cremoris

1991

View full text Add to dashboard Cite

The replication region of pSK11L, the lactose plasmid of Lactococcus lactis subsp. cremoris (L. Plasmid replication and stability have been extensively studied for several plasmids found in gram-negative species. These studies have led to identification of several plasmidencoded elements which mediate plasmid replication, control plasmid copy number, and stabilize plasmid inheritance (18,24,26,30 the reasons for the differing abilities of L. lactis and L. cremoris strains to maintain pSK11L, we attempted to identify the pSK11L replication origin and regions involved in plasmid maintenance since these regions would be most likely to interact with host plasmid replication and maintenance functions.We report here that a 14.8-kbp PvuII fragment of pSK11L confers the replication ability and the temperature-sensitive pSK11L maintenance phenotype of L. lactis LM0230. We also report identification of several regions on this fragment which appear to affect pSK11L maintenance. Several of these regions affect pSK11L maintenance differently in L. lactis LM0230 and L. cremoris EB5. MATERIALS AND METHODSBacterial strains and plasmids. The L. lactis strains used in this study included LM0230, a plasmid-free, prophage-free derivative of C2 (9), and JF3216, an LM0230 transformant containing pSK11L, a lactose plasmid from L. cremoris SK11 (10). The L. cremoris strain used was EB5, a plasmidfree derivative of KR1 (3). Strains LM0230 and EB5 were grown at 32°C in M17 broth (33) supplemented with 0.5% glucose (M17-G). Transformants derived from these strains were grown at 25°C in M17-G containing erythromycin (Em) (10 jig/ml). Strain JF3216 was grown at 25°C in M17 broth supplemented with 0.5% lactose. The Escherichia coli plasmid used to clone the replication region of pSK11L was pVA891, a derivative of pACYC184 (4) containing the pAM,1 Emr-encoding gene (21). pVA891 and its derivatives were maintained in E. coli XL1-Blue

show abstract

Section: Resultssupporting

confidence: 84%

Section: Resultsmentioning

confidence: 99%

Replication and temperature-sensitive maintenance functions of lactose plasmid pSK11L from Lactococcus lactis subsp. cremoris

1991

View full text Add to dashboard Cite

show abstract

“…Plasmid DNA was subjected to electrophoresis on a 0-7 % agarose gel (0-5 volts/mm for 2-5 h) and transferred on to the membrane by the method of Southern (1975). A 2-4 kb EcoRl/Xhol fragment (Yu et al 1989) containing the phospho-/?-galactosidase gene from Ladococcus ladis subsp. cremoris H2, a 34 kb Hindlll fragment containing 88% of the /?-galactosidase gene from Str.…”

Section: Dna Methodsmentioning

confidence: 99%

Growth of lactic acid bacteria and bifidobacteria on lactose and lactose-related mono-, di- and trisaccharides and correlation with distribution ofβ–galactosidase and phospho-β–galactosidase

Smart

Pillidge

Garman

1993

Journal of Dairy Research

View full text Add to dashboard Cite

SummarySpectrophotometric assays ofβ–galactosidase (EC 3.2.1.23) and phospho-β–galactosidase (EC 3.2.1.85) activity were used to survey the lactose utilization pathways of lactic acid bacteria and bifidobacteria.β–Galactosidase activity was found in all six genera represented (Lactococcus, Streptococcus, Leuconostoc, Lactobacillus, PediococcusandBifidobacterium) while phospho-β–galactosidase was restricted to the lactococci, twoLactobacillusand twoLeuconostocspecies. A number of strains ofLactococcus lactis, Lactobacillus caseiandLeuconostocspp. contained both enzymes. Enzyme activities varied when cells were grown on different sugars, but in general were low or absent for cells grown on glucose compared with lactose. Two lactose-related compounds, lactulose and galactosyl lactose, believed to be specific growth factors for bifidobacteria, supported growth amongst a wide range of lactic acid bacteria in addition to bifidobacteria. Growth on galactosyl lactose was restricted to some but not all strains containingβ–galactosidase, implying that the presence ofβ–galactosidase is insufficient by itself to ensure utilization of galactosyl lactose. DNA fragments that encoded theLactococcus lactissubsp.cremorisphospho-β–galactosidase gene or theβ–galactosidase genes ofStreptococcus salivariussubsp.thermophilusorLactobacillus delbrueckiisubsp.bulgaricuswere isolated and used as probes in DNA-DNA hybridizations. Little or no hybridization was detected between these probes and plasmid or genomic DNA isolated from heterologous species, despite the presence of the corresponding enzyme activity in the strains probed.

show abstract

“…We used the vectors pFX4, pFX5 and pFX6 to generate functional fl-gal fusions with fragments containing the galactose-6-phosphate isomerase and proteinase genes from the lactococcal plasmid pDI-21 [18,21]. The 2.0 kb EcoRI fragment of pDI-21 which showed homology with a galactose-6-phosphate isomerase gene probe had previously expressed no enzymatic activity in E. coli [20].…”

Section: Translation Fusion Uectors Constructionmentioning

confidence: 99%

Construction of a family of lactococcal vectors for gene cloning and translational fusion

Xu¹

1991

FEMS Microbiology Letters

View full text Add to dashboard Cite

Restriction mapping and localization of the lactose-metabolizing genes of Streptococcus cremoris pDI-21

Cited by 10 publications

References 16 publications

Replication and temperature-sensitive maintenance functions of lactose plasmid pSK11L from Lactococcus lactis subsp. cremoris

Replication and temperature-sensitive maintenance functions of lactose plasmid pSK11L from Lactococcus lactis subsp. cremoris

Growth of lactic acid bacteria and bifidobacteria on lactose and lactose-related mono-, di- and trisaccharides and correlation with distribution ofβ–galactosidase and phospho-β–galactosidase

Construction of a family of lactococcal vectors for gene cloning and translational fusion

Contact Info

Product

Resources

About