beta-Ketoacyl-ACP synthase I of Escherichia coli: nucleotide sequence of the fabB gene and identification of the cerulenin binding residue

The fabB gene of E. coli encoding beta-ketoacyl-ACP synthase I has been isolated by complementation and sequenced. The enzyme has been purified and its NH2-terminal residues sequenced. Identification of the active site was accomplished by tagging with 3H-cerulenin and radio sequencing of the region. Comparison of the deduced primary structures of the fabB gene product with the FAS2 gene product of Saccharomyces cerevisiae revealed the probable active site in chalcone synthases of higher plants.

Homologous domains in Trichoderma reesei cellulolytic enzymes: gene sequence and expression of cellobiohydrolase II

Fungal cellobiohydrolases are unique enzymes capable of degrading highly ordered crystalline cellulose. We present here the isolation and complete sequence analysis of the chromosomal and cDNA copies of the structural gene (cbh2) coding for one of the major cellobiohydrolases (CBH II) of Trichoderma reesei. We also present data on expression of the cbh2 gene and show that the transcription start points of the cbh2 gene are heterogeneous and are located 32 to 52 bp downstream from a putative TATA box. The derived CBH II protein sequence is 471 amino acids long and the coding region is interrupted by three short introns. Most of the CBH II protein bears no apparent resemblance to CBH I and endoglucanase I. However, a short region of extensive homology is found in all Trichoderma cellulases characterized so far, suggesting that this region is important for cellulose hydrolysis. The implications of this information with regard to the evolution of fungal cellulase genes and the enzymology of cellulose hydrolysis are discussed.

Construction and identification of a cDNA clone for human type II procollagen mRNA

Double-stranded cDNA was constructed for poly(A)-containing RNA isolated from foetal human articular cartilage known to contain small amounts of pro alpha 1 (II) collagen mRNA. A 585 base pair PstI-EcoRI cDNA fragment was isolated and cloned into plasmid pBR322. A resulting recombinant plasmid pHCAR1 was shown to hybridize specifically to a 5.4 kilobase mRNA in cartilage but not in calvarial RNA. Definite identification of clone pHCAR1 was based on sequence analysis; marked homology with the corresponding chick gene and complete agreement with the human gene sequences available were observed.