Leishmania (Sauroleishmania) tarentolae isolation and sympatric occurrence with Leishmania (Leishmania) infantum in geckoes,dogs and sand flies

The trypanosomatid protist Leishmania tarentolae is a saurian-associated parasite vectored by the Sergentomyia minuta sand fly. This study aimed to confirm the circulation of L. infantum and L. tarentolae in sand flies, reptiles and dogs and to isolate new strains of these protists. Reptilian and sheltered dog blood samples were collected, and sand flies were captured. Samples were tested for Leishmania spp. using duplex real-time PCR (dqPCR) and real-time PCR (qPCR); the origin of blood meal was identified in engorged sand flies by conventional PCR. The reptilian blood and intestinal content of sand fly females were cultured. Dog sera were tested by IFAT using both Leishmania species. Four Tarentola mauritanica geckoes were molecularly positive for L. infantum or L. tarentolae, with no co-infections; moreover, amastigote-like forms of L. infantum were observed in the bone marrow. 24/294 sand flies scored positive for Leishmania spp. by dqPCR, 21 S. minuta and two Phlebotomus perniciosus were positive for L. tarentolae, while only a single Ph. perniciosus was positive for L. infantum. Blood meal analysis confirmed reptile and dog in S. minuta, dog and human in Ph. perniciosus and dog in Phlebotomus neglectus. Two axenic strains of L. tarentolae were obtained. Twelve of 19 dogs scored positive for L. infantum and L. tarentolae by IFAT and three of them also for L. infantum by dqPCR, and six by qPCR. These data confirm the sympatric circulation of L. infantum and L. tarentolae in geckoes, sand flies, and dogs, and suggest that geckoes may be infected with L. infantum.     

The tipuloid dipterans (Diptera,Tipulidae, Limoniidae) from the Putorana Plateau,with a description of Dactylolabis tschernovi sp. n.

The first data are presented on the tipuloid dipterans from the Putorana Plateau, the Central Siberian Plateau: the crane-flies, Tipula (Arctotipula) oklandi Al., Tipula (Pterelachisus) tundrensis stackelbergiana Lack., Tipula (Vestiplex) arctica Curt., and Tipula (Yamatotipula) lionota Holm.; and the limoniids, Dactylolabis (Dactylolabis) novaezemblae (Al.) and Dactylolabis (Dactylolabis) tschernovi sp. n. A new species, Dactylolabis (D.) tschernovi sp. n., is described from the adult males and females. The male of the new species is very similar to those of Dactylolabis (Dactylolabis) carbonaria Sav. and Dactylolabis (Dactylolabis) satanas Sav. but can be distinguished from the former by the presence of a distinct throat, by the coloration of the head, femora, tibiae, and abdominal segments, as well as by the spear-shaped interbase of the hypopygium; and from the latter species, by the fully developed wings and by the absence of large spines at the base of the interbases.     

Enantiomeric Composition of the trans-Dihydrodiols Produced from Phenanthrene by Fungi

The trans-dihydrodiols produced during the metabolism of phenanthrene by Cunninghamella elegans, Syncephalastrum racemosum, and Phanerochaete chrysosporium were purified by high-performance liquid chromatography (HPLC). The enantiomeric compositions and optical purities of the trans-dihydrodiols were determined to compare interspecific differences in the regio- and stereoselectivity of the fungal enzymes. Circular dichroism spectra of the trans-dihydrodiols were obtained, and the enantiomeric composition of each preparation was analyzed by HPLC with a chiral stationary-phase column. The phenanthrene trans-1,2-dihydrodiol produced by C. elegans was a mixture of the 1R,2R and 1S,2S enantiomers in variable proportions. The phenanthrene trans-3,4-dihydrodiol produced by P. chrysosporium was the optically pure 3R,4R enantiomer, but that produced by S. racemosum was a 68:32 mixture of the 3R,4R and 3S,4S enantiomers. The phenanthrene trans-9,10-dihydrodiol produced by P. chrysosporium was predominantly the 9S,10S enantiomer, but those produced by C. elegans and S. racemosum were predominantly the 9R,10R enantiomer. The results indicate that although different fungi may exhibit similar regioselectivity, there still may be differences in stereoselectivity that depend on the species and the cultural conditions.     

Xiphidorus amazonensis n. sp. (Nematoda: Longidoridae) from the Brazilian Amazon Basin

Xiphidorus amazonensis n. sp. was found in the rhizospheres of Jatropha curcas, Musa sp., Anona muricata, Cassia tora, Panicum laxum, Paspalum fasciculatum, Aeschynomene sensitiva, Saccharum officinarum, Manihot esculenta, Abelmoschus esculentus, Tamarindus indica, Mangifera indica, Vigna unguiculata, Zea mays, Commelina sp., Cyperus rotundus, Fimbristylis miliacea, Citrus sinensis, and Eichhornia crassipes on the Amazon River island of Xiborena, approximately 40 km southeast of Manaus, capital of the State of Amazonas. The type habitat is flooded annually for about 6 months by the Amazon River. Xiphidorus amazonensis n. sp. differs from the closely related species Xiphidorus yepesara Monteiro, 1976 by the larger size, by a, b, and c values, and by the rounded tail terminus. It also resembles Xiphidorus tucumanensis Chaves and Coomans, 1984, but can be distinguished by its larger size, larger a, b, and c values, more conical female tail, bilobed amphidial pouch, and the presence of a spermatheca full of sperm.     

Isolation and structural analyses of positional isomers of 61,6m-di-O-α-d-mannopyranosyl-cyclomaltooctaose (m=2–5) and 6-O-α-(n-O-α-d-mannopyranosyl)-α-d-mannopyranosyl-cyclomaltooctaose (n=2, 3, 4, and 6)

Eight positional isomers of 6¹,6^m-di-O-α-d-mannopyranosyl-cyclomaltooctaose (γCD) (m=2–5) and 6-O-α-(n-O-α-d-mannopyranosyl)-d-mannopyranosyl-γCD (n=2, 3, 4, and 6) in a mixture of products from γCD and d-mannose by condensation reaction of α-mannosidase from jack bean were isolated by HPLC. The structures of four isomers of 6-O-α-(n-O-α-d-mannopyranosyl)-d-mannopyranosyl-γCD were elucidated by NMR spectroscopy. On the other hand, four positional isomers of 6¹,6^m-di-O-α-d-mannopyranosyl-γCD were determined by LC–MS analysis of degree of polymerization of the branched oligosaccharides produced by enzymatic degradation with bacterial saccharifying α-amylase (BSA), and combination of BSA and glucoamylase. Similarly cyclomaltodextrin glucanotransferase also digested these isomers.     

Proliferating cell nuclear antigen in the cytoplasm interacts with components of glycolysis and cancer

Proliferating cell nuclear antigen (PCNA) is involved in a wide range of functions in the nucleus. However, a substantial amount of PCNA is also present in the cytoplasm, although their function is unknown. Here we show, through Far-Western blotting and mass spectrometry, that PCNA is associated with several cytoplasmic oncoproteins, including elongation factor, malate dehydrogenase, and peptidyl-prolyl isomerase. Surprisingly, PCNA is also associated with six glycolytic enzymes that are involved in the regulation of steps 4-9 in the glycolysis pathway.

Structured summary

MINT-7995351: G3P (uniprotkb:P04406) and PCNA (uniprotkb:P12004) colocalize (MI:0403) by fluorescencemicroscopy (MI:0416)MINT-7995334: ENOA (uniprotkb:P06733) and PCNA (uniprotkb:P12004) colocalize (MI:0403) by fluorescencemicroscopy (MI:0416)MINT-7995368: ALDOA (uniprotkb:P04075) and PCNA (uniprotkb:P12004) colocalize (MI:0403) by fluorescencemicroscopy (MI:0416)MINT-7995141: G3P (uniprotkb:P04406) binds (MI:0407) to PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995182: ENOA (uniprotkb:P06733) binds (MI:0407) to PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995132: G3P (uniprotkb:P04406) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995228: PRDX6 (uniprotkb:P30041) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995220: CAH2 (uniprotkb:P00918) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995114: Triosephosphateisomerase (uniprotkb:P60174) binds (MI:0407) to PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995244: K2C7 (uniprotkb:P08729) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995252: ANXA2 (uniprotkb:P07355) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995122: Triosephosphateisomerase (uniprotkb:P60174) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995093: ALDOA (uniprotkb:P04075) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995148: PGK1 (uniprotkb:P00558) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995158: PGAM1 (uniprotkb:P18669) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995166: PGAM1 (uniprotkb:P18669) binds (MI:0407) to PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995105: ALDOA (uniprotkb:P04075) binds (MI:0407) to PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995260: PPIA (uniprotkb:P62937) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995173: ENOA (uniprotkb:P06733) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995268: EF1A (uniprotkb:P68104) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995236: MDHM (uniprotkb:P40926) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995189: RSSA (uniprotkb:P08865) physicallyinteracts (MI:0915) with PCNA (uniprotkb:P12004) by farwesternblotting (MI:0047)MINT-7995282: PCNA (uniprotkb:P12004) physicallyinteracts (MI:0915) with ALDOA (uniprotkb:P00883) and G3P (uniprotkb:P46406) by antibaitcoimmunoprecipitation (MI:0006).     

Synthesis of D-manno-3-heptulose,D-ido-3-heptulose,and some aldoheptoses via isopropylidene derivatives of heptitols

D-manno-3-Heptulose (5) was synthesized by dimethyl sulfoxide-phosphorus pentaoxide oxidation of 1,2:3,4:6,7-tri-O-isopropylidene-D-glycero-D-manno-heptitol (3, prepared from volemitol), followed by hydrolysis. D-ido-3-Heptulose (8) was synthesized similarly by oxidation of 1,2:4,5:6,7-tri-O-isopropylidene-D-glycero-l-galacto-heptitol (7, prepared from D-glycero-l-galacto-heptitol, 6). Another tri-O-isopropylidene derivative (11), having a free primary hydroxyl group, was produced in larger amount than 7, and 11 yielded D-glycero-l-galacto-heptose (14). Compound 8 was also synthesized by way of 1,2:4,5.6,7-tri-O-isopropylidene-D-glycero-l-gulo-heptitol (15). The production of 15 from D-glycero-l-gulo-heptitol (13) was accompanied by a larger amount of 2,3:4,5:6,7-tri-O-isopropylidene-D-glycero-D-ido-heptitol (17) which, upon oxidation followed by hydrolysis, yielded D-glycero-D-ido-heptose (18). One of the two tri-O-isopropylidene derivatives obtained by acetonation of perseitol, 2,3:4,5:6,7-tri-O-isopropylidene-D-glycero-D-galacto-heptitol (19), yielded D-glycero-D-galacto-heptose (20).     

Relative Abundance and Plasmodium Infection Rates of Malaria Vectors in and around Jabalpur,a Malaria Endemic Region in Madhya Pradesh State,Central India

BackgroundThis study was undertaken in two Primary Health Centers (PHCs) of malaria endemic district Jabalpur in Madhya Pradesh (Central India).MethodsIn this study we had investigated the relative frequencies of the different anopheline species collected within the study areas by using indoor resting catches, CDC light trap and human landing methods. Sibling species of malaria vectors were identified by cytogenetic and molecular techniques. The role of each vector and its sibling species in the transmission of the different Plasmodium species was ascertained by using sporozoite ELISA.ResultsA total of 52,857 specimens comprising of 17 anopheline species were collected by three different methods (39,964 by indoor resting collections, 1059 by human landing and 11,834 by CDC light trap). Anopheles culicifacies was most predominant species in all collections (55, 71 and 32% in indoor resting, human landing and light trap collections respectively) followed by An. subpictus and An. annularis. All five sibling species of An. culicifacies viz. species A, B, C, D and E were found while only species T and S of An. fluviatilis were collected. The overall sporozoite rate in An. culicifacies and An. fluviatilis were 0.42% (0.25% for P. falciparum and 0.17% for P. vivax) and 0.90% (0.45% for P. falciparum and 0.45% for P. vivax) respectively. An. culicifacies and An. fluviatilis were found harbouring both P. vivax variants VK-210 and VK-247, and P. falciparum. An. culicifacies sibling species C and D were incriminated as vectors during most part of the year while sibling species T of An. fluviatilis was identified as potential vector in monsoon and post monsoon season.ConclusionsAn. culicifacies species C (59%) was the most abundant species followed by An. culicifacies D (24%), B (8.7%), E (6.7%) and A (1.5%). Among An. fluviatilis sibling species, species T was common (99%) and only few specimens of S were found. Our study provides crucial information on the prevalence of An. culicifacies and An. fluviatilis sibling species and their potential in malaria transmission which will assist in developing strategic control measures against these vectors.     

Characterization of Labeled Residues from 5-Diazouracil-2-C Incorporated into Ribonucleic Acids of Filamentous Escherichia coli

E. coli B, filamented with 5-diazouracil (DZU)-2-¹⁴C, yielded ribonucleic acid (RNA)-(DZU-2-¹⁴C) which was converted by pancreatic ribonuclease to ¹⁴C-mono-and oligo-nucleotides. The mixed ¹⁴C-mononucleotides isolated by diethylaminoethyl-cellulose fractionation were identified as cytidylic, uridylic, and hydroxyuridylic acids, by using a combination of paper chromatography and treatment with alkaline phosphatase and cytidine deaminase. Rifampin blocked incorporation of DZU-2-¹⁴C under conditions which inhibit RNA synthesis. Division inhibition by DZU-2-¹⁴C and the incorporation into Escherichia coli B were retarded by uracil but not by other RNA bases. In a pyrimidine-requiring E. coli, DZU substituted for uracil or cytosine to an extent limited by toxic effects. Cytosine and uracil retarded these effects and retarded the incorporation of DZU-2-¹⁴C into the pyrimidineless strain. A small proportion of DZU-2-¹⁴C was converted by the latter strain into hydroxyuridylic acid, but the bulk of the incorporated label was in cytidylic and uridylic acid, as in the wild strain.     

Revision of the wingless Sikkimia Duvivier (Coleoptera,Chrysomelidae, Galerucinae) from Taiwan,including a new generic synonymy and four new species descriptions

The genus Taiwanolepta Kimoto, 1989 (type species Taiwanolepta babai Kimoto, 1989) is proposed as a junior synonym of Sikkimia Duvivier, 1891. Sikkimia species from Taiwan form a group characterized by the reduction of their hind wings. Most of them cannot be distinguished using external morphology, except by the structure of last two antennomeres in males. Diagnoses are made by using distribution, aedeagal, and gonocoxal morphology. The group includes one previously described species, Sikkimia babai (Kimoto, 1989), comb. n., and four new species, Sikkimia meihuai sp. n., Sikkimia sufangae sp. n., Sikkimia tsoui sp. n., and Sikkimia yuae sp. n. Speciation models, supporting the high diversity of Sikkimia species in Taiwan, are discussed. Sikkimia metallica Jacoby, 1903 and Sikkimia tamra Maulik, 1936, both from southern India, are transferred to the genus Cerophysa Chevrolat, 1836.     

S100 proteins interact with the N-terminal domain of MDM2

S100 proteins interact with the transactivation domain and the C-terminus of p53. Further, S100B has been shown to interact with MDM2, a central negative regulator of p53. Here, we show that S100B bound directly to the folded N-terminal domain of MDM2 (residues 2-125) by size exclusion chromatography and surface plasmon resonance experiments. This interaction with MDM2 (2-125) is a general feature of S100 proteins; S100A1, S100A2, S100A4 and S100A6 also interact with MDM2 (2-125). These interactions with S100 proteins do not result in a ternary complex with MDM2 (2-125) and p53. Instead, we observe the ability of a subset of S100 proteins to disrupt the extent of MDM2-mediated p53 ubiquitylation in vitro.

Structured summary

MINT-7905256: MDM2 (uniprotkb:Q00987) binds (MI:0407) to s100A6 (uniprotkb:P06703) by surface plasmon resonance (MI:0107)MINT-7905063: MDM2 (uniprotkb:Q00987) and s100A1 (uniprotkb:P23297) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905376: s100A4 (uniprotkb:P26447) and MDM2 (uniprotkb:Q00987) physically interact (MI:0915) by competition binding (MI:0405)MINT-7905130: s100A6 (uniprotkb:P06703) and MDM2 (uniprotkb:Q00987) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905207: s100A6 (uniprotkb:P06703) and p53 (uniprotkb:P04637) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905043: s100B (uniprotkb:P04271) and MDM2 (uniprotkb:Q00987) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905196: p53 (uniprotkb:P04637) and s100A4 (uniprotkb:P26447) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905358: p53 (uniprotkb:P04637) and s100A4 (uniprotkb:P26447) physically interact (MI:0915) by fluorescence polarization spectroscopy (MI:0053)MINT-7905220: MDM2 (uniprotkb:Q00987) binds (MI:0407) to s100B (uniprotkb:P04271) by surface plasmon resonance (MI:0107)MINT-7905104: s100A4 (uniprotkb:P26447) and MDM2 (uniprotkb:Q00987) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905229: MDM2 (uniprotkb:Q00987) binds (MI:0407) to s100A1 (uniprotkb:P23297) by surface plasmon resonance (MI:0107)MINT-7905317, MINT-7905162: s100B (uniprotkb:P04271) and p53 (uniprotkb:P04637) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905238: MDM2 (uniprotkb:Q00987) binds (MI:0407) to s100A2 (uniprotkb:P29034) by surface plasmon resonance (MI:0107)MINT-7905174, MINT-7905308: s100A1 (uniprotkb:P23297) and p53 (uniprotkb:P04637) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905247: MDM2 (uniprotkb:Q00987) binds (MI:0407) to s100A4 (uniprotkb:P26447) by surface plasmon resonance (MI:0107)MINT-7905090: s100A2 (uniprotkb:P29034) and MDM2 (uniprotkb:Q00987) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905142, MINT-7905326: MDM2 (uniprotkb:Q00987) and p53 (uniprotkb:P04637) bind (MI:0407) by molecular sieving (MI:0071)MINT-7905185, MINT-7905347: s100A2 (uniprotkb:P29034) and p53 (uniprotkb:P04637) bind (MI:0407) by molecular sieving (MI:0071)     

A new species of the genus Nihonotrypaea Manning & Tamaki, 1998 (Crustacea,Decapoda, Axiidea,Callianassidae) from the South China Sea

A new species of the genus Nihonotrypaea Manning & Tamaki, 1998, Nihonotrypaea hainanensis sp. n., collected from the South China Sea, is described and illustrated. It is distinguishable from Nihonotrypaea harmandi (Bouvier, 1901), Nihonotrypaea japonica (Ortmann, 1891), Nihonotrypaea thermophila Lin, Komai & Chan, 2007 and Nihonotrypaea makarovi Martin, 2013 by having the elongated carpus of the male and female major cheliped. The new species is distinguishable from Nihonotrypaea petalura (Stimpson, 1860) by the proximolower margin of the carpus of the male major cheliped bearing several small denticles.     

Analysis of the Bacillus subtilis recO gene: RecO forms part of the RecFLOR function

The deduced protein product of the Bacillus subtilis gene yqfI, which is 255 residues long, shares homology (25% identity) with the Escherichia coli RecO protein. A null allele of yqfI, when present in an otherwise Rec⁺ B. subtilis strain, causes cells to become highly sensitive to DNA-damaging agents, and plasmid transformation (intramolecular recombination) is reduced by 25-fold while chromosomal transformation (intermolecular recombination) is only moderately affected (2.5-fold reduction). Therefore, the yqfI gene was renamed recO and its null allele is referred to as recO1. The recO1 mutation was introduced into recombination-deficient strains representative of the epistatic groups α (recF, recR and recL strains), β (addA5 addB72), γ (recH342) and ? (recU40). The recO mutation did not affect the sensitivity of recF, recR or recL cells to DNA-damaging agents, increased the sensitivity of recU and addAB cells and abolished the DNA repair capacity of recH cells. The recO mutation did not affect intermolecular recombination in recF, recL, recH or recU cells, but reduced (by about 9-fold) the incidence of intermolecular recombination in addAB cells. The recO mutation did not affect intramolecular recombination in the addAB, recU, recF or recL cells, but reduced it by about 75-fold in recH cells. The defects caused by the recO1 mutation can be partially suppressed by a common suppressor of the recF, recL and recR phenotypes. We therefore assigned recO to epistatic group α and predict that the RecO protein acts at the same stage of recombination as the RecF, RecL and RecR proteins, in a RecFLOR complex.     

Assimilation of E. coli cells by Daphnia magna on the whole organism level

Consumption of E. coli cells by Daphnia magna was studied. It was found that this organism not only ingested E. coli cells but digested them as demonstrated by the release of ¹⁴CO₂ originating from E. coli grown on ¹⁴C-glucose, and by the transfer of the radioactive label from parental Daphnia to their progenies. In addition the effect of antibiotics on the consumption of E. coli cells by Daphnia magna was studied. In long incubation times, antibiotics inhibited bacterial uptake by Daphnia. The microflora isolated from Daphnia was found to be capable of causing leakage of enzymes out of E. coli cells thus playing at least a partial role in the digestion of E. coli cells by Daphnia.     

Proteome Analysis Identifies the Dpr Protein of Streptococcus mutans as an Important Factor in the Presence of Early Streptococcal Colonizers of Tooth Surfaces

Oral streptococci are primary colonizers of tooth surfaces and Streptococcus mutans is the principal causative agent of dental caries in humans. A number of proteins are involved in the formation of monospecies biofilms by S. mutans. This study analyzed the protein expression profiles of S. mutans biofilms formed in the presence or absence of S. gordonii, a pioneer colonizer of the tooth surface, by two-dimensional gel electrophoresis (2-DE). After identifying S. mutans proteins by Mass spectrometric analysis, their expression in the presence of S. gordonii was analyzed. S. mutans was inoculated with or without S. gordonii DL1. The two species were compartmentalized using 0.2-μl Anopore membranes. The biofilms on polystyrene plates were harvested, and the solubilized proteins were separated by 2-DE. When S. mutans biofilms were formed in the presence of S. gordonii, the peroxide resistance protein Dpr of the former showed 4.3-fold increased expression compared to biofilms that developed in the absence of the pioneer colonizer. In addition, we performed a competition assay using S. mutans antioxidant protein mutants together with S. gordonii and other initial colonizers. Growth of the dpr-knockout S. mutans mutant was significantly inhibited by S. gordonii, as well as by S. sanguinis. Furthermore, a cell viability assay revealed that the viability of the dpr-defective mutant was significantly attenuated compared to the wild-type strain when co-cultured with S. gordonii. Therefore, these results suggest that Dpr might be one of the essential proteins for S. mutans survival on teeth in the presence of early colonizing oral streptococci.     

In situ adaptation and ecological release facilitate the occupied niche expansion of a non‐native Madagascan day gecko in Florida

AimTo investigate whether the frequently advocated climate‐matching species distribution modeling approach could predict the well‐characterized colonization of Florida by the Madagascar giant day gecko Phelsuma grandis.LocationMadagascar and Florida, USA.MethodsTo determine the climatic conditions associated with the native range of P. grandis, we used native‐range presence‐only records and Bioclim climatic data to build a Maxent species distribution model and projected the climatic thresholds of the native range onto Florida. We then built an analogous model using Florida presence‐only data and projected it onto Madagascar. We constructed a third model using native‐range presences for both P. grandis and the closely related parapatric species P. kochi.ResultsDespite performing well within the native range, our Madagascar Bioclim model failed to identify suitable climatic habitat currently occupied by P. grandis in Florida. The model constructed using Florida presences also failed to reflect the distribution in Madagascar by overpredicting distribution, especially in western areas occupied by P. kochi. The model built using the combined P. kochi/P. grandis dataset modestly improved the prediction of the range of P. grandis in Florida, thereby implying competitive exclusion of P. grandis by P. kochi from habitat within the former''s fundamental niche. These findings thus suggest ecological release of P. grandis in Florida. However, because ecological release cannot fully explain the divergent occupied niches of P. grandis in Madagascar versus Florida, our findings also demonstrate some degree of in situ adaptation in Florida.Main conclusionsOur models suggest that the discrepancy between the predicted and observed range of P. grandis in Florida is attributable to either in situ adaptation by P. grandis within Florida, or a combination of such in situ adaptation and competition with P. kochi in Madagascar. Our study demonstrates that climate‐matching species distribution models can severely underpredict the establishment risk posed by non‐native herpetofauna.     

两栖动物性别决定相关基因的研究进展

两栖动物的性别决定机制主要包括遗传性别决定(genetic sex determination,GSD)和环境性别决定(environmental sex determination,ESD).近年来,在两栖动物性别决定和性腺分化机制的研究中,运用分子生物学技术探讨性别决定相关基因及其相互关系方面的研究已获得新的成果....