• Journal of Microbiology and Biotechnology
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• v.25 no.1
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• pp.127-136
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• 2015

Cupredoxin-like proteins are mainly copper-binding proteins that conserve a typical rigid Greek-key arrangement consisting of an eight-stranded β-sandwich, even though they share as little as 10-15% sequence similarity. The electron transport function of the Cupredoxins is critical for respiration and photosynthesis, and the proteins have therapeutic potential. Despite their crucial biological functions, the identification of the distant Cupredoxin homologs has been a difficult task due to their low sequence identity. In this study, the overlapped conserved residue (OCR) fingerprint for the Cupredoxin superfamily, which consists of conserved residues in three aspects (i.e., the sequence, structure, and intramolecular interaction), was used to detect the novel Cupredoxin homologs in the NCBI non-redundant protein sequence database. The OCR fingerprint could identify 54 potential Cupredoxin sequences, which were validated by scanning them against the conserved Cupredoxin motif near the Cu-binding site. This study also attempted to model the 3D structures and to predict the functions of the identified potential Cupredoxins. This study suggests that the OCR-based approach can be used efficiently to detect novel homologous proteins with low sequence identity, such as Cupredoxins.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.186-191
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• 1994

The origin of the leading strand replication (ori) and of lagging strand replication (M-O) of R-plasmid pSBK203 was identified and its base sequence was determined. About 50 bp of ori sequence residues overlapped with the structural gene of rep. Sequence comparison reveals that pSBK-ori shares obvious identities with those of pT181 family and consists of two regions, one is conserved and the other is variable region. Of two palindrome sequence located one after another in upstream region of rep gene, palA' instead of palA which shares sequence homology with diverse family of plasmids such as pOX6, pC194, and pE194 seems to act as a signal for conversion of primarily replicated ssDNA to dsDNA (minus origin (M-O)).