scholarly journals Cloning and sequencing of protochlorophyllide reductase

1990 ◽  
Vol 265 (3) ◽  
pp. 789-798 ◽  
Author(s):  
P M Darrah ◽  
S A Kay ◽  
G R Teakle ◽  
W T Griffiths

Putative protochlorophyllide reductase cDNA clones (252 and 113) were isolated from an etiolated-oat (Avena sativa) cDNA library. These were used to indirectly characterize a further clone, p127, isolated from a lambda-phage gt11 cDNA library. The latter (1.15 kb in length) was sequenced, and the derived amino acid sequence was shown to be remarkably similar to that derived from chemical analysis of a CNBr-cleavage fragment of the purified reductase, p127 codes for more than 95% of the reductase protein.

1989 ◽  
Vol 259 (1) ◽  
pp. 283-290 ◽  
Author(s):  
W M Abbott ◽  
A Mellor ◽  
Y Edwards ◽  
T Feizi

A full-length cDNA clone for the 13-14 kDa soluble beta-galactoside-binding lectin was isolated from a bovine fibroblast cDNA library. The derived amino acid sequence shows eight differences from a preliminary partial amino acid sequence given previously for the bovine heart lectin. This observation led to a re-examination of the data and correction of the heart lectin protein sequence. Except for a possible polymorphism of the heart lectin at position 57, the fibroblast and heart lectin sequences are considered identical. The epitope recognized by two monoclonal anti-(bovine lectin) antibodies, 36/8 and 9/5, was identified as the tetrapeptide sequence W-G-A/S-E/D by the isolation of several different cDNA clones from a human intestine cDNA library. A similar tetrapeptide is present in all of the soluble beta-galactoside-binding animal lectins sequenced thus far. It is also found in myelin basic protein, which we show is antigenically cross-reactive with the lectin. In myelin basic protein the tetrapeptide is a part of the major domain previously shown to be responsible for the induction of experimental allergic encephalomyelitis.


1995 ◽  
Vol 15 (7) ◽  
pp. 3759-3766 ◽  
Author(s):  
N Takamatsu ◽  
H Kanda ◽  
I Tsuchiya ◽  
S Yamada ◽  
M Ito ◽  
...  

SRY-related cDNA encoding a protein with a high-mobility-group (HMG) box and a leucine zipper motif, which was designated SOX-LZ, was isolated from a rainbow trout testis cDNA library. Comparison of this cDNA with the mouse homologous cDNA isolated from a testis cDNA library exhibits an overall amino acid sequence identity of 77%, which is in striking contrast to the abrupt loss of amino acid sequence homology outside the HMG box found among mammalian SRY genes. In both rainbow trout and mice, Northern (RNA) blot analyses have revealed the presence of a testis-specific 3-kb-long SOX-LZ mRNA, and this transcript appeared coincidentally with the protamine mRNA, suggesting its expression in the germ line. A recombinant HMG box region protein encoded by SOX-LZ could bind strongly with an oligonucleotide containing an AACAAT sequence, which is also recognized by mouse Sry and Sox-5. Upon cotransfection into CHO cells, SOX-LZ transactivated transcription through its binding motif when the region including the leucine zipper motif was deleted [SOX-LZ (D105-356)]; however, the intact SOX-LZ failed to transactivate. The intact SOX-LZ could form homodimers through the leucine zipper, which resulted in inhibition of DNA binding by the HMG box, while SOX-LZ (D105-356), which was incapable of dimerization, showed specific binding with the AACAAT sequence. Thus, the repressed transactivation of the intact SOX-LZ in CHO cells was primarily attributable to the low level of DNA binding of SOX-LZ homodimers.


1986 ◽  
Vol 236 (1) ◽  
pp. 115-126 ◽  
Author(s):  
G A Russell ◽  
B Dunbar ◽  
L A Fothergill-Gilmore

The complete amino acid sequence of chicken skeletal-muscle enolase, comprising 433 residues, was determined. The sequence was deduced by automated sequencing of hydroxylamine-cleavage, CNBr-cleavage, o-iodosobenzoic acid-cleavage, clostripain-digest and staphylococcal-proteinase-digest fragments. The presence of several acid-labile peptide bonds and the tenacious aggregation of most CNBr-cleavage fragments meant that a commonly used sequencing strategy involving initial CNBr cleavage was unproductive. Cleavage at the single Asn-Gly peptide bond with hydroxylamine proved to be particularly useful. Comparison of the sequence of chicken enolase with the two yeast enolase isoenzyme sequences shows that the enzyme is strongly conserved, with 60% of the residues identical. The histidine and arginine residues implicated as being important for the activity of yeast enolase are conserved in the chicken enzyme. Secondary-structure predictions are analysed in an accompanying paper [Sawyer, Fothergill-Gilmore & Russell (1986) Biochem. J. 236, 127-130].


1995 ◽  
Vol 305 (2) ◽  
pp. 439-444 ◽  
Author(s):  
T M Johnson ◽  
H P Kocher ◽  
R C Anderson ◽  
G M Nemecek

Two overlapping cDNA clones encoding pigeon liver carnitine acetyltransferase (EC 2.3.1.7) (CAT) were isolated from a pigeon liver lambda gt11 cDNA library by gene amplification using oligonucleotide primers based on the N-terminal amino acid sequence of the enzyme. The two clones, which represent the 5′ and 3′ ends of the gene, were spliced together to form a single cDNA construct containing the entire coding sequence for CAT, with an in-frame TGA stop codon 42 bases before the first ATG start site and a 3′-untranslated segment of 1057 bases. The largest open reading frame of 1942 nucleotides predicted a polypeptide of 627 amino acids and a molecular mass of 71.1 kDa. The N-terminus and four internal peptides from the amino acid sequence of pigeon breast muscle CAT were identified in the predicted sequence of the liver cDNA clone. The identity of the CAT cDNA was confirmed by heterologous expression of active recombinant CAT (rCAT) in insect cells using the baculovirus expression system. Western blots of rCAT from infected insect cell lysates and immunodetection with a rabbit anti-CAT polyclonal serum showed an immunoreactive protein band similar in size to native CAT from pigeon breast muscle. Like the native enzyme, rCAT was capable of acylating carnitine with a preference for small-chain acyl-CoAs of carbon chain lengths C2-C4.


Blood ◽  
1991 ◽  
Vol 78 (7) ◽  
pp. 1826-1833 ◽  
Author(s):  
LE Toothaker ◽  
DA Gonzalez ◽  
N Tung ◽  
RS Lemons ◽  
MM Le Beau ◽  
...  

Abstract We have isolated 5′ cDNA clones encoding a member of the cellular myosin heavy chain gene family from human leukocytes. The predicted amino acid sequence shows 93% identity to a chicken cellular myosin heavy chain, 76% to chicken smooth muscle, and 40% to human sarcomeric myosin heavy chain. The mRNA is expressed as a 7.4- to 7.9-kb doublet in many nonmuscle cells, and is upregulated in myeloid cell lines on induction from a proliferating to a differentiated state. Antisera raised against a peptide made from the predicted amino acid sequence specifically reacts with a 224-Kd polypeptide in leukocyte cell lines, and the protein is also upregulated during the induction of monocytic and granulocytic differentiation in these cells. The gene for this cellular myosin heavy chain maps to chromosome 22, bands q12.3-q13.1, demonstrating that it is not located in the previously described sarcomeric gene clusters on chromosomes 14 and 17. This cellular myosin heavy chain may be a major contractile protein responsible for movement in myeloid cell lines because no mRNA for sarcomeric myosin heavy chain is detected in these cells.


1992 ◽  
Vol 287 (2) ◽  
pp. 639-643 ◽  
Author(s):  
M S Reddy ◽  
L A Bobek ◽  
G G Haraszthy ◽  
A R Biesbrock ◽  
M J Levine

The low-molecular-mass human salivary mucin has at least two isoforms, MG2a and MG2b, that differ primarily in their sialic acid and fucose content. In this study, we characterize further these isoforms, particularly their peptide moieties. Trypsin digests of MG2a and MG2b yielded high- and low-molecular-mass glycopeptides following gel filtration on Sephacryl S-300. The larger glycopeptides from MG2a and MG2b had similar amino acid compositions and identical N-terminal sequences, suggesting common structural features between their peptides. An oligonucleotide probe generated from the amino acid sequence of the smaller glycopeptide from MG2a was employed in Northern-blot analysis. This probe specifically hybridized to two mRNA species from human submandibular and sublingual glands. A cDNA clone selected from a human submandibular gland cDNA expression library with antibody generated against deglycosylated MG2a also hybridized to these two mRNA species. In both cases, the larger mRNA was polydisperse, and the hybridization signal was more intense in the sublingual gland. In addition, the N-terminal amino acid sequence of the larger glycopeptide was found to be part of one of the selected MG2 cDNA clones.


Sign in / Sign up

Export Citation Format

Share Document