Lactobacillus bulgaricus (Luerssen et Kühn) Holland

Summary From the results of the experiments described, as well as from the literature, it becomes clear that the definition ofLactobacillus bulgaricus given in Bergey's Manual should be altered. This bacterium produces laevorotatory (D) lactic acid almost exclusively and ferments a limited number of sugars only,e.g. not maltose, saccharose or trehalose. All strains grew in a medium with 2% sodium chloride but no appreciable growth occurred with 4%, nor with 2% sodium taurocholate.     

Antibacterial sensitivity of Bifidobacterium (Lactobacillus bifidus)

The presence of the altered lysine transfer ribonucleic acid (tRNA) in Bacillus subtilis spores is strongly dependent on the medium on which the cells were sporulated. Cells sporulated on synthetic media or dilute complex media contain little or none of the new component, whereas those sporulated on concentrated complex media accumulate the altered tRNA. The accumulation begins during the fifth or sixth stage of sporulation, the formation of the tunic, and the appearance of refractility, respectively. Mutants blocked early in sporulation differ in their ability to accumulate the altered tRNA when cultured on the same complex medium. Of the four mutants examined, one failed to accumulate any of the RNA, whereas a second contained the full complement characteristic of spores. The third and fourth mutant contained small amounts of the material. It is tentatively concluded that the accumulation of the altered lysine tRNA is not obligate to sporulation but is an epiphenomenon of the process.     

Temporal temperature gradient gel electrophoresis (TTGE) as a tool for identification of Lactobacillus casei, Lactobacillus paracasei, Lactobacillus zeae and Lactobacillus rhamnosus

AIMS: To develop a tool for rapid and inexpensive identification of the Lactobacillus casei complex. METHODS AND RESULTS: Lactobacillus casei, Lactobacillus paracasei, Lactobacillus zeae and Lactobacillus rhamnosus were identified by PCR-amplification of the segment between the U1 and U2 regions of 16S rDNA (position 8-357, Escherichia coli numbering) and temporal temperature gradient gel electrophoresis (TTGE). Seven tested Lact. paracasei strains were divided into three TTGE-subgroups. CONCLUSION: TTGE successfully distinguished between the closely-related target species. TTGE is also a powerful method for revealing sequence heterogeneities in the 16S rRNA genes. SIGNIFICANCE AND IMPACT OF THE STUDY: Due to rapid and easy performance, TTGE of PCR-amplified 16S rDNA fragments will be useful for the identification of extended numbers of isolates.     

Evaluation of random amplified polymorphic DNA (RAPD)-PCR as a method to differentiate Lactobacillus acidophilus,Lactobacillus crispatus,Lactobacillus amylovorus,Lactobacillus gallinarum,Lactobacillus gasseri,and Lactobacillus johnsonii

The technique random amplified polymorphic DNA (RAPD)-PCR was evaluated as a method to differentiate Lactobacillus acidophilus, Lactobacillus crispatus, Lactobacillus amylovorus, Lactobacillus gallinarum, Lactobacillus gasseri, and Lactobacillus johnsonii. Representative strains, including the type of each species, were selected from different clusters obtained by numerical analysis of total soluble cell protein patterns. Results obtained by RAPD-PCR corresponded well with results obtained by numerical analysis of total soluble cell protein patterns. The type strains of each species displayed different RAPD profiles. Strains with identical L(+)- nicotinamide adenine dinucleotide-dependent lactic dehydrogenase (nLDH) electrophoretic profiles could be distinguished on the basis of their RAPD profiles.     

Über den Stoffwechsel und die Cellulosesynthese von Acetobacter xylinum (Brown) Holland

Ohne ZusammenfassungTeil 1 einer Dissertation der Fakultät für Chemie, Biologie, Geologie und Mineralogie der Technischen Hochschule Darmstadt.     

唾液乳杆菌的研究进展

唾液乳杆菌属于乳杆菌科、乳杆菌属,广泛地存在于人和动物的肠道。近年来,唾液乳杆菌作为益生菌广泛用于人和动物益生菌制剂的生产。在分析与唾液乳杆菌相关的文献和生物信息数据的基础上,就唾液乳杆菌的生物学特征、作用机制、应用及发展前景进行了简要综述,为唾液乳杆菌的研究提供参考。     

d-(-)-Mandelic acid dehydrogenase from Lactobacillus curvatus

Summary Production, purification and characterization of the NAD(H)-dependent d-mandelate dehydrogenase from Lactobacillus curvatus was studied. An enzyme level of about 150 U/1 could be obtained by anaerobic cultivation in liquid broth. The specific enzyme activity in the crude extract was 1—3 U/mg. Purification by liquidliquid extraction and ion exchange chromatography led to a preparation of 2100 U/mg. The molecular weight of the enzyme was determined to be 60000 (gel filtration on Superose S12) containing two subunits of 30000. A variety of aliphatic and aromatic -keto acids are accepted as substrates by the mandelate dehydrogenase, for the substrate benzoylformate a Michaelis constant of 2·10^-4M was measured. Cu²⁺-ions and mercury compounds such as HgCl₂ or p-chloromercuribenzoate are strong inhibitors at concentrations of 0.1 mM. An unoptimized continuous conversion in an enzyme-membrane-reactor demonstrated that the enzyme could be applied for the stereospecific synthesis of d-mandelic acid.Abbreviations FDH formate dehydrogenase - PEG polyethylenglycol - SDS sodiumdodecylsulfate - MRS growth medium according to deMan, Rogosa and Sharpe (deMan et al. 1960)     

Taxonomic note "Lactobacillus pastorianus" (Van Laer, 1892) a former synonym for Lactobacillus paracollinoides

"Lactobacillus pastorianus" (Van Laer, 1892) is not a validly described species and is not included in the Approved List of Bacterial Names. The strain is available in multiple culture collections as Lactobacillus sp. DSM 20197, L. brevis ATCC 8291, "L. pastorianus" CECT 5926, L. brevis JCM 1113, and "L. pastorianus" LMG 11990. Nearly identical 16S rRNA sequences and protein encoding genes for 6-phosphogluconate dehydrogenase (99.9%) revealed this strain as L. paracollinoides. A 16S-23S rRNA intergenic spacer region-based PCR assay did not differentiate "L. pastorianus" DSM 20197 from L. paracollinoides DSM 15502(T). Highly similar RAPD profiles differentiated both strains below species level.     

Conjugal plasmid transfer (pAM beta 1) in Lactobacillus plantarum

The streptococcal plasmid pAM beta 1 (erythromycin resistance) was transferred via conjugation from Streptococcus faecalis to Lactobacillus plantarum and was transferred among L. plantarum strains. Streptococcus sanguis Challis was transformed with pAM beta 1 isolated from these transconjugants, and transformants harboring intact pAM beta 1 could conjugate the plasmid back to L. plantarum.     

Fourier transform infrared (FTIR) spectroscopy for identifying Lactobacillus species

Abstract Fourier Transform infrared (FTIR) spectroscopy can be used to identify microorganisms. This study describes the influence of culture conditions on FTIR spectra and the discrimination of Lactobacillus species found in breweries. Fifty three Lactobacillus strains were analysed by FTIR spectroscopy and identification at the species level was correct for 94% of the strains, and at the strain level for 91% of the strains.