Evaluation of GABA Production and Probiotic Activities of Enterococcus faecium BS5

Probiotics and Antimicrobial Proteins - Gamma-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter in the central nervous system and is produced by irreversible decarboxylation of...     

Endobacterial morphotypes in nudibranch cerata tips: a SEM analysis

The SEM investigation of nudibranch cerata material exhibits endobacterial morphotypes found in 12 out of 13 species tested: Aeolidia papillosa, Berghia caerulescens, Coryphella brownii, Coryphella lineata, Coryphella verrucosa, Cuthona amoena, Facelina coronata, Flabellina pedata, Dendronotus frondosus, Doto coronata, Tritonia plebeia and Janolus cristatus. Endobacteria could not be detected inside Tritonia hombergi. Endobacterial morphology found inside nudibranch species was compared to bacterial morphotypes detected earlier in tentacles of cnidarian species. SEM micrographs show endobacterial analogy among nudibranch species, but also similarity to cnidarian endobacteria investigated earlier. Of course, morphological data of microbes do not allow their identification. However, since most of these nudibranch species prey on cnidaria, it cannot be excluded that many of the endobacteria detected inside nudibranch species may originate from their cnidarian prey. Our previous data describing genetic affiliation of endobacteria from nudibranchian and cnidarian species support this assumption. Dominant coccoid endobacteria mostly exhibit smooth surface and are tightly packed as aggregates and/or wrapped in envelopes. Such bacterial aggregate type has been described previously in tentacles of the cnidarian species Sagartia elegans. Similar coccoid bacteria, lacking envelopes were also found in other nudibranch species. A different type of coccoid bacteria, characterized by a rough surface, was detected inside cerata of the nudibranch species Berghia caerulescens, and surprisingly, inside tentacles of the cnidarian species Tubularia indivisa. In contrast to cnidarian endobacteria, rod-shaped microorganisms are largely absent in nudibranch cerata.     

Sexual selection and animal personality

Consistent individual behavioural tendencies, termed “personalities”, have been identified in a wide range of animals. Functional explanations for personality have been proposed, but as yet, very little consideration has been given to a possible role for sexual selection in maintaining differences in personality and its stability within individuals. We provide an overview of the available literature on the role of personality traits in intrasexual competition and mate choice in both human and non‐human animals and integrate this into a framework for considering how sexual selection can generate and maintain personality. For this, we consider the evolution and maintenance of both main aspects of animal personality: inter‐individual variation and intra‐individual consistency.     

Bacterial community in the tunic matrix of a colonial ascidian<Emphasis Type="Italic"> Diplosoma migrans</Emphasis>

This paper provides the first information on the morphology of different morphotypes of bacteria in the tunic matrix of the colonial ascidian Diplosoma migrans. Ascidians were collected from waters near Helgoland (German Bight, North Sea). The dominant type is represented by extremely high numbers of long, needle-like rods (length 10–30 µm, width 0.5 µm). The bacteria are motile by means of bipolar monotrichous flagella, generating swift sigmoidal movement. Bacteria are already present during different embryonic stages. It is assumed that they are transferred during sexual propagation from the parental colony to its offspring. As a second morphotype, the tunic harbors screw-like bacteria in low numbers (length 4–10 µm, width 0.5 µm). Besides these conspicuous morphotypes, occasionally motile rods with spore-like globules at one end and additional coccoid forms in large quantities of unknown meaning (possibly spores) were found. The taxonomic status and ecological functions of these differently shaped bacterial groups are unclear.Communicated by H.-D. Franke     

Monolayer formation of human osteoblastic cells on vertically aligned multiwalled carbon nanotube scaffolds

Monolayer formation of SaOS‐2 (human osteoblast‐like cells) was observed on VACNT (vertically aligned multiwalled carbon nanotubes) scaffolds without purification or functionalization. The VACNT were produced by a microwave plasma chemical vapour deposition on titanium surfaces with nickel or iron as catalyst. Cell viability and morphology studies were evaluated by LDH (lactate dehydrogenase) release assay and SEM (scanning electron microscopy), respectively. The non‐toxicity and the flat spreading with monolayer formation of the SaOs‐2 on VACNT scaffolds surface indicate that they can be used for biomedical applications.     

Bacterial aggregates in the tentacles of the sea anemone <Emphasis Type="Italic">Metridium senile</Emphasis>

This paper provides first information on organ-like bacterial aggregates in the tentacles of the sea anemone Metridium senile. The specimens were collected from waters near Helgoland (German Bight, North Sea) and the Orkney Islands. Tentacles were prepared for morphological inspection by light and scanning electron microscopy as well as for the phylogenetic analysis of endocytic bacteria. Bacterial aggregates are located in caverns of the tentacles’ epidermis. The aggregates are enwrapped in thin envelopes, which contain coccoid and/or rod-shaped tightly packed bacteria of different division states. Most of the bacterial cells are connected by fine filamentous structures. The phylogenetic determination is based on the sequence data of the 16S rDNA derived from tentacle material. Sequence analysis revealed three different subgroups of intratentacular proteobacteria. The dominant band, detected in all of the samples tested, showed a close relationship (98%) to a gram-negative Endozoicimonas elysicola. Two bands, only detected in tentacles of M. senile from Helgoland were assigned to Pseudomonas saccherophilia (99%), a knallgas bacterium, and to Ralstonia pickettii (100%). The bacteria represent a specific bacterial community. Their DGGE profiles do not correspond to the profiles of the planktonic bacteria generated from seawater close to the habitats of the anemones. The allocation of DNA sequences to the different morphotypes, their isolation, culturing and the elucidation of the physiological functions of intratentacular bacteria are in progress.     

Peri/nuclear localization of intact insulin-like growth factor binding protein-2 and a distinct carboxyl-terminal IGFBP-2 fragment in vivo

Insulin-like growth factor binding protein-2 (IGFBP-2) as one of the most important IGFBPs has never been assessed in the intracellular compartment in vivo. Since there is evidence for novel intracellular functions of distinct IGFBPs, we investigated the presence of IGFBP-2 inside the cell. In peri/nuclear fractions of various tissues isolated from IGFBP-2 transgenic and non-transgenic mice we were able to show the presence of intact IGFBP-2. In addition, we demonstrate the presence of a highly conserved carboxyl-terminal IGFBP-2 fragment in the peri/nuclear fraction by using different peptide-induced antibodies. In pancreatic sections, confocal microscopy revealed the presence of IGFBP-2 on the nuclear surface but not within the nucleus. Our findings suggest novel functions of intact IGFBP-2 and IGFBP-2 fragments within the cell.     

Successive virgin births of viable male progeny in the checkered gartersnake,Thamnophis marcianus

In recent years genotyping analysis using mini‐ and microsatellite markers has provided robust DNA‐based support for facultative parthenogenesis (FP) in several lineages of squamate reptiles (snakes and lizards) and sharks. Rather than incidental cases of reproductive error, there is growing evidence that FP is an alternative reproductive strategy and an important mode of reproduction in these phylogenetically divergent vertebrate groups. Because documentation of FP in vertebrates is in its infancy, additional instances supported by molecular genetic methods provide insights that advance our general understanding of this phenomenon. Here, in a female checkered gartersnake (Thamnophis marcianus) reared in isolation since a juvenile, we describe five successive parthenogenetic litters produced over a 7‐year period that resulted in several viable male progeny. Cross species microsatellite amplification was performed across 30 primer pairs derived from Thamnophis spp. and related natricines to the female and nine available progeny. Five loci proved heterozygous in the maternal sample with the progeny differentially homozygous at all but one locus. Combined with evidence pertaining to captive history and litter characteristics, our analysis supports a specific type of FP, terminal fusion automictic parthenogenesis, over the competing hypothesis of long‐term sperm storage. Importantly, we document that a single individual was capable of producing successive litters composed of live parthenogens. In two cases, males achieved adulthood and showed the anatomical potential to demonstrate reproductive competence (normal looking hemipenes and testes). © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 107 , 566–572.     

Immunophenotyping of human HT29 colon cancer cell primary tumours and their metastases in severe combined immunodeficient mice

The immunophenotype of HT29 human colon cancer cells implanted into severe combined immunodeficient mice was assessed in primary tumours and their metastases in the lungs using an indirect immunohistochemical method. After primary tumours were surgically removed, the metastases were given time to develop, thus paralleling the clinical situation. While vimentin was negative in both primary and secondary tumours, E-cadherin was present as membrane-bound labelling in the primary tumours only. Whereas the markers p53, MIB1, PCNA and CEA were consistently positive in both primary and metastatic tumours, CD44 variant 6 and CA125 were negative in metastases but positive in the primary tumours. There was a significant increase in the percentage of cells labelled for p53 in the primary tumours compared with the metastases. For the proliferation markers, there was no significant difference in labelling between primary tumours and metastases for MIB1. Of the cytokeratins examined, CK 20 gave the strongest and most consistent reaction in both primary and secondary tumours. The results indicate that, for certain immunohistochemical markers, results are the same in both primary tumours and metastases. Hence, in these cases, antigens that are expressed on the primary tumour as well as on the metastases can serve as target molecules for immunologically based forms of treatment of metastases. This revised version was published online in November 2006 with corrections to the Cover Date.