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C Lemieux

Publications and source records attributed to C Lemieux.

At least 55 records · Page 3Linked to original sources
PubMed1995

Structure-activity relationships of dermorphin analogues containing N-substituted amino acids in the 2-position of the peptide sequence.

A series of dermorphin analogues containing an N-alkylated amino-acid residue Xaa in the 2-position of the peptide sequence was synthesized (Xaa = N-methylalanine, proline, pipecolic acid, N-methylphenylalanine, 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid [Tic]). These peptides have the potential of assuming a cis Tyr1-Xaa2 peptide bond. Their in vitro opioid activity profiles were determined in mu- and delta-receptor-representative binding assays and bioassays. Aside from [D-Pro2]dermorphin, all analogues showed high affinity for mu- and/or delta-opioid receptors. Whereas most compounds were found to be full mu-agonists in the guinea pig ileum (GPI) assay, [Tic2]dermorphin (compound 7) was a partial mu-agonist. Replacement of Gly4 in 7 with Phe resulted in an analogue (8) with weak mu-antagonist activity. Furthermore, analogues 7 and 8 both were potent delta-antagonists (Ke = 3-40 nM) against the delta-agonists Leu-enkephalin, DPDPE and deltorphin I in the mouse vas deferens (MVD) assay. Compound 3, containing L-Pro in the 2-position, turned out to be one of the most mu-receptor-selective linear dermorphin analogues reported to date. Low-temperature HPLC experiments using micropellicular octadecyl silica as stationary phase revealed conformational heterogeneity of the dermorphin analogues which was ascribed to cis-trans isomerization around the Tyr1-Xaa2- and Tyr5-Pro6 peptide bonds. In the case of analogue 7 four separate peaks corresponding to the four possible isomers were apparent at -5 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1994

The Chlamydomonas chloroplast clpP gene contains translated large insertion sequences and is essential for cell growth.

Sequence determination of the chloroplast clpP gene from two distantly related Chlamydomonas species (C. reinhardtii and C. eugametos) revealed the presence of translated large insertion sequences (IS1 and IS2) that divide the clpP gene into two or three sequence domains (SDs) and are not found in homologous genes in other organisms. These insertion sequences do not resemble RNA introns, and are not spliced out at the mRNA level. Instead, each insertion sequence forms a continuous open reading frame with its upstream and downstream sequence domains. IS1 specifies a potential polypeptide sequence of 286 and 318 amino acid residues in C. reinhardtii and C. eugametos, respectively. IS2 encodes a 456 amino acid polypeptide and is present only in C. eugametos. The two Chlamydomonas IS1 sequences show substantial similarity; however, there is no significant sequence similarity either between IS1 and IS2 or between these insertion sequences and any other known protein coding sequences. The C. reinhardtii clpP gene was further shown to be essential for cell growth, as demonstrated through targeted gene disruption by particle gun-mediated chloroplast transformation. Only heteroplasmic transformants could be obtained, even under mixotrophic growth conditions. The heteroplasmic transformants were stable only under selection pressure for the disrupted clpP, rapidly segregated into wild-type cells when the selection pressure was removed, and grew significantly more slowly than wild-type cells under phototrophic conditions.

ATP-Dependent Proteases↗
PubMed1994

Cyclic beta-casomorphin analogues with mixed mu agonist/delta antagonist properties: synthesis, pharmacological characterization, and conformational aspects.

Analogues of the potent and moderately mu-opioid-receptor-selective cyclic beta-casomorphin-5 derivative H-Tyr-c[-D-Orn-Phe-D-Pro-Gly-] (2) were prepared by conventional solution synthesis. Replacement of the Phe3 residue by 2-naphthylalanine (2-Nal) led to a peptide (4) with high affinity for both mu and delta opioid receptors. This compound turned out to be an agonist in the mu-receptor-representative guinea pig ileum (GPI) assay but a moderately potent antagonist against various delta agonists in the delta-receptor-representative mouse vas deferens (MVD) assay. It thus represents the first known cyclic opioid peptide analogue with mixed mu agonist/delta antagonist properties. Interestingly, replacement of 2-Nal3 in compound 4 with 1-naphthylalanine (1-Nal) resulted in an analogue (5) showing high affinity for mu receptors and a full agonist effect in the MVD assay that was mediated by both mu and delta receptors. Substitution of Trp for Phe3 in 2 (compound 8) was well tolerated at both receptors and led to an analogue with agonist activity in both the GPI and MVD assays. Variation of the peptide ring size in 4 was achieved by substitution of D-Orn2 with D-Lys (compound 6) or D-2,4-diaminobutyric acid (compound 7). Analogue 6 was also a mixed mu agonist/delta antagonist with somewhat lower potency than 4, whereas compound 7 displayed mu agonist and partial delta agonist properties. Further reduction of the peptide ring size, as achieved by deletion of the Gly5 residue, produced a compound (9) which was a full agonist in both bioassays. Conformational analysis of analogues 2, 4, and 5 by 1H NMR spectroscopy and molecular mechanics studies suggested that the overall conformation of parent compound 2 and the 2-Nal-containing peptide 4 was similar, while the side-chain orientation of 1-Nal in peptide 5 was different. These results suggest that the delta antagonist properties of analogue 4 may not be due to a difference in its overall conformation as compared to the agonist 2 but may be a direct effect of the 2-naphthyl moiety per se preventing proper alignment of the peptide for receptor activation.

Amino Acid Sequence↗
PubMed1994

The I-CeuI endonuclease: purification and potential role in the evolution of Chlamydomonas group I introns.

During genetic crosses between the interfertile green algae Chlamydomonas eugametos and Chlamydomonas moewusii, the I-CeuI endonuclease encoded by the fifth group I intron (CeLSU.5) in the C. eugametos chloroplast large subunit rRNA gene mediates the mobility of this intron by introducing a double-strand break near the insertion site of the intron in the corresponding C. moewusii intronless allele. To characterize the biochemical properties of this endonuclease, we have purified I-CeuI and determined the optimal reaction conditions for cleavage. I-CeuI activity is maximal at 50 degrees C, pH 10.0, 2.5 mM MgCl2 and in the absence of NaCl. Unlike the well-characterized I-SceI endonuclease, I-CeuI remains stable following preincubation in the absence of substrate. We discuss the role that homing endonucleases may have played in the evolution of Chlamydomonas chloroplast group I introns.

Animals↗
PubMed1994

Modification of flower color in florist's chrysanthemum: production of a white-flowering variety through molecular genetics.

Chimeric chalcone synthase (CHS) constructs were prepared in both anti-sense and sense orientations, and introduced into the chrysanthemum cultivar Moneymaker, along with a T-DNA vector lacking a CHS construct. For both the anti-sense and sense constructs, the majority of the plants produced pink flowers typical of Moneymaker itself. Of 133 sense and 83 anti-sense transgenic individuals 3 of each set produced fully white or very pale pink flowers. No white-flowering transgenic plants were obtained in control transformations. The white flowers were found to accumulate higher levels of chalcone synthase precursors and to have reduced levels of chalcone synthase message. A small-scale field trial was performed to evaluate the stability of the phenotype throughout a series of vegetative propagation steps and during plant growth. The white-flowering trait was maintained well through vegetative propagation; however, during growth of individual white-flowering plants, some pink color was found in some flowers. At one site 2% of the white-flowering plants produced a few pink flowers; at two other sites, as many as 10-12% of the plants produced pale pink flowers.

Acyltransferases↗
PubMed1994

Identification of variability of ribosomal DNA spacer from Pseudomonas soil isolates.

The polymerase chain reaction was used to amplify the spacer region located between the 16S and 23S ribosomal RNA genes of strains of Pseudomonas fluorescens and Pseudomonas putida isolated from peat bog, canola field, or arctic plants. Some of spacer region of four of the P. fluorescens strains examined, strains 64-3, 63-28, QP5, and R17-FP2, was about 515 base pairs (bp) in length, and contained the genes for tRNA(Ile) and tRNA(Ala). The DNA sequences of two strains from canola, 64-3 and 63-28, differed at only two positions. The sequences of the peat bog strains QP5 and R17-FP2 were identical. However, differences were noted between the DNA sequence common to the pair of strains 64-3 and 63-28 and the corresponding common sequence for strains QP5 and R17-FP2. These differences were mainly concentrated in two DNA segments of 10 and 19 bp, respectively. A probe for the 19-bp variable segment that occurs in the ribosomal spacer of strains QP5 and R17-FP2 recognized total DNA from these two strains, but not DNA from other bacteria of different origins. These results suggest the existence of a limited degree of variability within the 16S-23S ribosomal DNA spacer region, and that this variability may be useful to the recognition of particular Pseudomonas strains from environmental samples.

Base Sequence↗
PubMed1993

TIPP[psi]: a highly potent and stable pseudopeptide delta opioid receptor antagonist with extraordinary delta selectivity.

Pseudopeptide analogues of the delta opioid antagonists H-Tyr-Tic-Phe-Phe-OH (TIPP) and H-Tyr-Tic-Phe-OH (TIP) containing a reduced peptide bond between the Tic2 and Phe3 residues were synthesized. The two compounds, H-Tyr-Tic psi [CH2NH]Phe-Phe-OH (TIPP [psi]) and H-Tyr-Tic psi-[CH2NH]Phe-OH (TIP [psi]), were tested in mu-, delta-, and kappa-receptor-selective binding assays and in the guinea pig ileum (GPI) and mouse vas deferens (MVD) bioassays. In comparison with their respective parent peptides, both pseudopeptide analogues showed increased delta antagonist potency in the MVD assay, higher delta receptor affinity and further improved delta receptor selectivity. The more potent compound, TIPP [psi], displayed subnanomolar delta receptor affinity and in direct comparisons with other selective delta ligands was shown to have unprecedented delta specificity (Ki mu/Ki delta = 10,500). Furthermore, this compound turned out to be highly stable against enzymatic degradation and, unlike other delta antagonists, showed no mu or kappa antagonist properties. TIPP [psi] is likely to find wide use as a pharmacological tool in opioid research.

Animals↗
PubMed1993

Analysis of the chloroplast large subunit ribosomal RNA gene from 17 Chlamydomonas taxa. Three internal transcribed spacers and 12 group I intron insertion sites.

Previous reports on the chloroplast large subunit rRNA genes of the two distantly related green algae Chlamydomonas eugametos and Chlamydomonas reinhardtii indicate differences in the distribution of group I introns and suggest a different arrangement of internal transcribed spacers. To provide insights into the origin of these two types of intervening sequences, we have undertaken the sequencing of the chloroplast rrnL genes of 15 additional Chlamydomonas taxa and have characterized the mature large subunit rRNA species they encode in addition to those specified by the C. reinhardtii rrnL. These analyses disclosed the presence of three internal transcribed spacers sharing the same positions in all of the 17 taxa as well as the presence of a total of 39 group I introns representing 12 insertion sites. Of these insertion sites, only one has been identified in non-Chlamydomonas taxa. The distribution of Chlamydomonas introns is highly variable and, in many respects, is not consistent with the phylogeny deduced from chloroplast rRNA sequence comparisons. This phylogeny features two main lineages of Chlamydomonas taxa forming sister groups. Because earlier branching organisms in the green algal/land plant lineage display no chloroplast rDNA introns, it appears that all of the intron insertion positions in Chlamydomonas are of recent origins, with some of the positions having arisen subsequent to the divergence of the two main Chlamydomonas lineages. Remarkably, the rRNA regions corresponding to most of the group I intron insertion positions in rRNA genes have been assigned functional roles suggesting that they lie in exposed regions of the ribosome. On the basis of this striking correlation between exposed rRNA regions and intron insertion sites, we speculate that the reversal of the self-splicing reaction has played a major role in the creation of the multiple intron insertion positions found in rRNA genes as well as in the proliferation of group I introns elsewhere in the Chlamydomonas chloroplast genome.

Animals↗
PubMed1993

The single group-I intron in the chloroplast rrnL gene of Chlamydomonas humicola encodes a site-specific DNA endonuclease (I-ChuI).

The single group-I intron (ChLSU.1) in the chloroplast (cp) large subunit rRNA-encoding gene (rrnL) of the green alga Chlamydomonas humicola is located at a position at which no introns have previously been characterized in other systems. In the present study, the nucleotide (nt) sequence of this 1118-bp intron was found to contain an internal open reading frame (ORF) that potentially encodes a basic protein of 218 amino acid residues. The putative C. humicola protein features two copies of the LAGLI-DADG motif and is part of the family of intron-encoded proteins comprising the endonucleases (ENases), I-SceI, I-SceIV and I-CsmI. Expression of the ChLSU.1 intron ORF in vitro in the presence of a 260-bp DNA fragment containing the exon 1-2 junction of an intronless version of the C. humicola rrnL resulted in specific cleavage of the DNA fragment very close to the intron insertion site. This novel intron-encoded ENase, designated I-ChuI, was also shown to generate a staggered cut with 4-nt (CTCG) 3'-OH overhangs 2 bp downstream from the intron insertion site.

Amino Acid Sequence↗
PubMed1992

Differential stereochemical requirements of mu vs. delta opioid receptors for ligand binding and signal transduction: development of a class of potent and highly delta-selective peptide antagonists.

Opioid peptide analogs consisting entirely of aromatic amino acid residues and containing conformationally restricted phenylalanine derivatives in position 2 of the peptide sequence were synthesized and pharmacologically characterized in vitro. Both diastereoisomers of H-Tyr-(D or L)-NMePhe-Phe-Phe-NH2 (NMePhe is N alpha-methylphenylalanine) were mu-receptor-selective, were full agonists in the mu-receptor-representative guinea pig ileum assay, and were partial agonists in the mouse vas deferens assay, with the L-NMePhe2 analog displaying somewhat higher intrinsic activity than the D-NMePhe2 analog. Further conformational restriction at position 2 in the sequence, as achieved through substitution of D- or L-tetrahydro-3-isoquinoline carboxylic acid (Tic), produced a configuration-dependent differential effect on receptor selectivity and intrinsic activity, leading to a potent mu-selective mu agonist (the D-Tic2 analog) with increased intrinsic activity in the mouse vas deferens assay and to a potent delta-selective delta antagonist (the L-Tic2 analog). These results demonstrate that imposition of conformational constraints in a peptide not only may alter receptor selectivity but also may decrease, totally abolish, or even enhance intrinsic activity. The tetrapeptide H-Tyr-Tic-Phe-Phe-NH2 was a moderately potent full agonist in the guinea pig ileum assay and, thus, represents a compound with mixed mu-agonist/delta-antagonist properties. The corresponding peptide with a free C-terminal carboxyl group H-Tyr-Tic-Phe-Phe-OH showed high delta-receptor affinity (Ki delta = 1.2 nM), unprecedented delta selectivity (Ki mu/Ki delta = 1410), high potency as delta antagonist (Ke = 3-8 nM against various delta agonists in the mouse vas deferens assay) and, unlike other delta antagonists, had no mu-antagonist properties. The tripeptides H-Tyr-Tic-Phe-OH and H-Tyr-Tic-Phe-NH2 were also delta antagonists.

Amino Acid Sequence↗
PubMed1992

The I-CeuI endonuclease recognizes a sequence of 19 base pairs and preferentially cleaves the coding strand of the Chlamydomonas moewusii chloroplast large subunit rRNA gene.

The I-CeuI endonuclease is a member of the growing family of homing endonucleases that catalyse mobility of group I introns by making a double-strand break at the homing site of these introns in cognate intronless alleles during genetic crosses. In a previous study, we have shown that a short DNA fragment of 26 bp, encompassing the homing site of the fifth intron in the Chlamydomonas eugametos chloroplast large subunit rRNA gene (Ce LSU.5), was sufficient for I-CeuI recognition and cleavage. Here, we report the recognition sequence of the I-CeuI endonuclease, as determined by random mutagenesis of nucleotide positions adjacent to the I-CeuI cleavage site. Single-base substitutions that completely abolish endonuclease activity delimit a 15-bp sequence whereas those that reduce the cleavage rate define a 19-bp sequence that extends from position -7 to position +12 with respect to the Ce LSU.5 intron insertion site. As the other homing endonucleases that have been studied so far, the I-CeuI endonuclease recognizes a non-symmetric degenerate sequence. The top strand of the recognition sequence is preferred for I-CeuI cleavage and the bottom strand most likely determines the rate of double-strand breaks.

Animals↗
PubMed1992

Conformationally restricted deltorphin analogues.

Conformationally restricted deltorphin analogues were synthesized either through incorporation of cyclic phenylalanine analogues in position 2 or 3 of the peptide sequence or through various side chain-to-side chain cyclizations. Compounds were tested in mu-, delta-, and kappa-receptor selective binding assays and in the guinea pig ileum (GPI) and mouse vas deferens (MVD) bioassays. Replacement of Phe3 in [D-Ala2]deltorphin I with 2-aminoindan-2-carboxylic acid (Aic) or L- or D-2-aminotetralin-2-carboxylic acid (Atc) resulted in agonist compounds which retained the high delta receptor selectivity of the parent peptide. Substitution of a tetrahydroisoquinoline-3-carboxylic acid (Tic) residue in the 2-position of [D-Ala2]deltorphin I and of [Phe4,Nle6]deltorphin produced a partial delta agonist, H-Tyr-Tic-Phe-Asp-Val-Val-Gly-NH2, and a pure delta antagonist, H-Tyr-Tic-Phe-Phe-Leu-Nle-Asp-NH2, respectively. The latter antagonist displayed high delta selectivity (Ki mu/Ki delta = 502) and was a potent antagonist against selective delta agonists in the MVD assay (Ke congruent to 10 nM). Various [D-Ala2]-deltorphin I analogues cyclized between the side chains of Orn (or Lys) and Asp (or Glu) residues substituted in positions 2 and 4, 4 and 7, and 2 and 7 were essentially nonselective. Comparison with corresponding N-terminal tetrapeptide analogues revealed that the C-terminal tripeptide segment in the deltorphin heptapeptides made a crucial contribution to delta affinity and delta selectivity in the case of the agonist peptides but not in the case of the antagonist.

Amino Acid Sequence↗
PubMed1992

Clinical usefulness of high-pressure liquid chromatographic determination of serum pentamidine in AIDS patients.

We have developed a reproducible HPLC method to determine serum pentamidine, which demonstrates good chromatographic performance, and is sensitive enough to measure therapeutic doses. Pentamidine is first extracted from serum by passage through a C-18 extraction cartridge. Potential interfering substances are then removed by washing with 100% methanol. Pentamidine is eluted from the extraction cartridge with 1-heptanesulfonic acid. The extract is chromatographed on a highly deactivated column for basic compounds in the presence of minimal concentrations of 1-heptanesulfonic acid as the pairing agent. Detection is by fluorescence. The method can determine serum pentamidine levels in the range of 15-600 ng/mL free of interference from other drugs. In monitoring pentamidine levels in AIDS patients with Pneumocystis carinii, we found that trough serum levels over 100 ng/mL were associated with toxicity (hypoglycemia or azotemia) in 100% of patients. With levels under 100 ng/mL, signs of toxicity were observed in only 29% of the patients. We conclude that dose adjustment based on serum levels reduces the incidence of toxicity and enhances pentamidine therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1992

High pentamidine levels associated with hypoglycemia and azotemia in a patient with Pneumocystis carinii pneumonia.

We report on a patient who presented with a Pneumocystis carinii pneumonia. Intravenous pentamidine (4 mg/kg/day) was given for 14 days without the occurrence of adverse effects. During this treatment, the mean (+/- SD) serum pentamidine trough concentration was 94 +/- 16 ng/ml. Three days later, the patient was admitted because of fever, and pentamidine (4 mg/kg/day) was again started. Fasting hypoglycemia and azotemia then occurred; the mean serum trough pentamidine level was 190 +/- 10 ng/ml during this week of treatment. We conclude that the occurrence of hypoglycemia and azotemia during pentamidine therapy may not be idiosyncrasic, but seemed associated in our patient with high levels of serum pentamidine.

AIDS-Related Opportunistic Infections↗
PubMed1992

Higher pentamidine levels in AIDS patients with hypoglycemia and azotemia during treatment of Pneumocystis carinii pneumonia.

Trimethoprim-sulfamethoxazole (TMP-SMZ) and pentamidine are both licensed for the treatment of Pneumocystis carinii pneumonia (PCP). However, their use is associated with various adverse side effects. In this prospective study, 26 AIDS patients with 32 episodes of PCP were treated with pentamidine (4 mg/kg/d). Each patient was treated for 12 to 21 days, depending on the rapidity of onset of the clinical response. During the 32 PCP episodes, hypoglycemia occurred in 16 instances, azotemia in 12, liver toxicity in 10, and leukopenia in 8. The occurrence of thrombopenia, leukopenia, and liver toxicity was not related to age, pentamidine levels, or other complications. However, patients who had hypoglycemia during pentamidine treatment had higher serum pentamidine levels than patients who did not have hypoglycemia (107 +/- 40 versus 70 +/- 26 ng/ml, p less than 0.004). In addition, we observed that patients with azotemia showed higher pentamidine levels during treatment (120 +/- 35 versus 64 +/- 22 ng/ml, p less than 0.001). In fact, 100% (11/11) of patients with serum pentamidine concentration greater than 100 ng/ml had fasting hypoglycemia and/or azotemia, while 33% (7/21) of those with pentamidine levels less than 100 ng/ml had these side effects (p less than 0.001). The relative risk of these complications with pentamidine levels greater than 100 ng/ml was 3 (95% confidence interval, 1.6 to 5.5). Fine-tuning the dose of pentamidine may eventually prove useful to avoid toxicity and optimize therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Cleavage pattern of the homing endonuclease encoded by the fifth intron in the chloroplast large subunit rRNA-encoding gene of Chlamydomonas eugametos.

The fifth group-I intron in the chloroplast large subunit rRNA-encoding gene of Chlamydomonas eugametos (CeLSU.5) is mobile during interspecific crosses between C. eugametos and Chlamydomonas moewusii. Like the six other mobile introns that have been well characterized so far, CeLSU.5 contains a long open reading frame (ceuIR) coding for a site-specific endonuclease (I-CeuI) that cleaves the C. moewusii intronless gene in the vicinity of the intron-insertion site. This stimulates gap repair and mediates efficient transfer of the intron at its cognate site. By expressing the ceuIR gene in the Escherichia coli vectors pKK233-2 and pTRC-99A, we recently demonstrated that the endonuclease is highly toxic to E. coli [Gauthier et al., Curr. Genet. 19 (1991) 43-47]. To eliminate this problem and characterize the cleavage pattern and recognition sequence of the I-CeuI endonuclease, we have expressed the ceuIR gene in E. coli under the control of a bacteriophage T7 promoter in a tightly regulated M13 system, and developed an in vitro system to assay partially purified I-CeuI activity. This allowed us to determine that I-CeuI recognizes a sequence of less than 26 bp centered around the insertion site and produces a staggered cut 5 bp downstream from this site, yielding 4-nucleotide (CTAA), 3'-OH overhangs.

Animals↗
PubMed1991

Six group I introns and three internal transcribed spacers in the chloroplast large subunit ribosomal RNA gene of the green alga Chlamydomonas eugametos.

The chloroplast large subunit rRNA gene of Chlamydomonas eugametos and its 5' flanking region encoding tRNA(Ile) (GAU) and tRNA(Ala) (UGC) have been sequenced. The DNA sequence data along with the results of a detailed RNA analysis disclosed two unusual features of this green algal large subunit rRNA gene: (1) the presence of six group I introns (CeLSU.1-CeLSU.6) whose insertion positions have not been described previously, and (2) the presence of three short internal transcribed spacers that are post-transcriptionally excised to yield four rRNA species of 280, 52, 810 and 1720 nucleotides, positioned in this order (5' to 3') in the primary transcript. Together, these RNA species can assume a secondary structure that is almost identical to that proposed for the 23 S rRNA of Escherichia coli. All three internal transcribed spacers map to variable regions of primary sequence and/or potential secondary structure, whereas all six introns lie within highly conserved regions. The first three introns are inserted within the sequence encoding the 810 nucleotide rRNA species and map within domain II of the large subunit rRNA structure; the remaining introns, found in the sequence encoding the 1720 nucleotide rRNA species, lie within either domain IV or V, as is the case for all other large subunit rDNA introns that have been documented to date. CeLSU.5 and CeLSU.6 each contain a long open reading frame (ORF) of more than 200 codons. While the CeLSU.6 ORF is not related to any known ORFs, the CeLSU.5 ORF belongs to a family of ORFs that have been identified in Podospora and Neurospora mitochondrial group I introns. The finding that a polymorphic marker showing unidirectional gene conversion during crosses between C. eugametos and Chlamydomonas moewusii is located within the CeLSU.5 ORF makes it likely that this intron is a mobile element and that its ORF encodes a site-specific endonuclease promoting the transfer of the intron DNA sequence.

Amino Acid Sequence↗