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Second language (L2) acquisition research has explored the acquisition of various syntactic constraints by L2 learners, one of which is "wanna" contraction. However, there is still a very limited body of research regarding the acquisition of "wanna" contraction, both in first language (L1) and L2. The purpose of the study is to examine adult L2 learners' knowledge of wanna contraction by using a grammaticality judgment task. Ninety-three Japanese learners of English took the grammaticality judgment task which consisted of 24 experimental items and 24 fillers, with a context provided. The experimental stimuli consisted of six conditions: Object extraction (e.g., "Who do you want to/wanna advise?"), subject extraction (e.g., "Who do you want to/*wanna advise Mary?"), and no extraction (e.g., "Do you want to/wanna advise Mary?"), all of which were presented with and without contraction. Subject extraction with contraction was the only ungrammatical condition. The participants were divided into three groups according to their English proficiency as measured by the cloze test: High level (JPN-H), intermediate level (JPN-I), and low level (JPN-L). The same grammaticality judgment task was also given to 41 native speakers of English in order to collect the baseline data. The results showed a proportional increase of learners who were correctly differentiating the contraction patterns and the decrease of those who were overgeneralizing the patterns over the three proficiency groups. This suggests a developmental pattern among the L2 learners with respect to the contraction constraint.

The LolCDE complex, an ATP-binding cassette (ABC) transporter, releases lipoproteins from the inner membrane, thereby initiating lipoprotein sorting to the outer membrane of Escherichia coli. The LolCDE complex is composed of two copies of an ATPase subunit, LolD, and one copy each of integral membrane subunits LolC and LolE. LolD hydrolyzes ATP on the cytoplasmic side of the inner membrane, while LolC and/or LolE recognize and release lipoproteins anchored to the periplasmic leaflet of the inner membrane. Thus, functional interaction between LolD and LolC/E is critically important for coupling of ATP hydrolysis to the lipoprotein release reaction. LolD contains a characteristic sequence called the LolD motif, which is highly conserved among LolD homologs but not other ABC transporters of E. coli. The LolD motif is suggested to be a region in contact with LolC/E, judging from the crystal structures of other ABC transporters. To determine the functions of the LolD motif, we mutagenized each of the 32 residues of the LolD motif and isolated 26 dominant-negative mutants, whose overexpression arrested growth despite the chromosomal lol[D.sup.+] background. We then selected suppressor mutations of the lolC and lolE genes that correct the growth defect caused by the LolD mutations. Mutations of the lolC suppressors were mainly located in the periplasmic loop, whereas ones of lolE suppressors were mainly located in the cytoplasmic loop, suggesting that the mode of interaction with LolD differs between LolC and LolE. Moreover, the LolD motif was found to be critical for functional interplay with LolC/E, since some LolD mutations lowered the ATPase activity of LolCDE without affecting that of LolD.

The classification of the bacterium, Aeromonas caviae W-61 to Paenibacillus sp. strain W-61 is cloned and expressed on the basis of the nucleotide sequence of the 16S rRNA gene emended and the xyn5 gene encoding xylanese 5 (Xyn5) in Escherichia coli. Findings concluded that Paenibacillus sp. strain W-61 Xyn5 is a cell surface anchored modular xylanase possessing a functional cellulose binding module and SLH domains.