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Mice transgenic for NPM-ALK develop non-Hodgkin lymphomas.

BACKGROUND: The t(2;5)(p23;q35) translocation is associated with a high percentage of anaplastic large-cell lymphomas (ALCL) of T- or null-cell phenotype. The translocation produces an 80 kDa hyperphosphorylated chimeric protein (p80) derived from the fusion of the anaplastic lymphoma kinase (ALK) with nucleophosmin (NPM). The NPM-ALK chimeric protein is an activated tyrosine kinase that has been shown to be a potent oncogene and presumably plays a causative role in lymphomagenesis. MATERIALS AND METHODS: A transgenic mouse line was generated, where the human NPM-ALK cDNA is driven by the lck promoter conferring transgene expression to early T-cells. RESULTS: Mice rapidly developed large cell lymphoblastic lymphomas with a median latency of 8 weeks, primarily involving the thymus, with lymph node as well as histologically evident extranodal organ infiltration by large tumor cells. CONCLUSION: The transgenic approach described provides direct evidence for the strong transforming potential of NPM-ALK in T-cells and furthermore represents a system for the analysis of the oncogenic events mediated by NPM-ALK in vivo, which might be instrumental in the development of tyrosine kinase inhibitor therapies of potential clinical use.

Animals↗

[Overexpression of NPM-ALK induces different types of malignant lymphomas in IL-9 transgenic mice].

Anaplastic large cell lymphoma (ALCL) comprises approximately 25 % of all non-Hodgkin lymphomas in children and young adults. 40% of these tumours have a translocation t(2;5)(p23;q35), which fuses the nucleophosmin gene (NPM) to the anaplastic lymphoma kinase gene (ALK) resulting in a hybrid protein which contributes to the pathogenensis of ALCL. To further analyse the transforming activity in an animal model, a cDNA encoding the protein product, NPM-ALK, was incorporated into a retrovirus construct and introduced into mouse bone marrow progenitors by infection. In a bone marrow gene transfer and transplantation protocol the hematopoietic compartments of lethally irradiated IL-9 transgenic mice were reconstituted with npm-alk infected progenitor cells. IL-9 transgenic mice were chosen, because IL-9, a pleiotropic T helper 2 cytokine, is expressed in most cases of human ALCL and was shown to have an oncogenic potential at least on T cells. Reconstituted mice developed NPM-ALK positive lymphomas including lymphoblastic lymphomas of T-cell type (T-LB), mature and immature plasmacytoma (PZ) and plasmoblastic/anaplastic diffuse large B-cell lymphoma after 10-30 weeks. The combined overexpression of NPM-ALK and IL-9 exerts cooperative oncogenic activity in the transformation of murine lymphoid cells leading to accelerated and enhanced development of T-LB. Many animals developed plasmacytic/plasmoblastic neoplasms, of which the most aggressive tumours share many features with human anaplastic/plasmoblastic diffuse large B-cell lymphoma.

Animals↗

Pediatric intracranial inflammatory myofibroblastic tumor harboring DCTN1::ALK fusion: a case report with radiologic-pathologic-molecular correlation.

Central nervous system inflammatory myofibroblastic tumors are rare; pediatric DCTN1::ALK fusion cases are exceptionally uncommon. Here, we present an eight-year-old boy who presented with headache, vomiting, and a rapidly enlarging right frontal scalp mass. An MRI showed a dural, extra-axial lesion with mass effect. Histology confirmed IMT, and ALK immunohistochemistry was positive; next-generation sequencing (NGS) identified DCTN1 (exon 1-27)-ALK (exon 20-29) fusion, and FISH confirmed ALK rearrangement (33/100 nuclei). Genomic metrics showed tumor mutational burden (TMB) of 0.94/Mb, microsatellite stability, and CNV burden of 2.1%. He underwent near total resection followed by alectinib; to our knowledge, this is the first reported young pediatric (<10&#xa0;years old) CNS IMT with this fusion.

Humans↗

ALK-negative systemic anaplastic large cell lymphoma: differential diagnostic and prognostic aspects--a review.

Anaplastic large cell lymphoma (ALCL) can be divided into two major groups. The first is a spectrum of CD30+ T-cell lymphoproliferative disorders including primary cutaneous ALCL and lymphomatoid papulosis, usually affecting older patients but characterized by an excellent prognosis. The second is systemic nodal ALCL, which on the basis of genetic and immunophenotypic features combined with clinical parameters can be divided into two subgroups: anaplastic lymphoma kinase (ALK)-positive and ALK-negative systemic ALCL. ALK expression, usually the result of a t(2;5) translocation, correlates with the expression of other markers such as EMA and a cytotoxic phenotype, and is strongly related to younger age groups, lower international prognostic index (IPI) risk groups, and a good prognosis. ALK-negative ALCL, however, shows a more heterogeneous immunophenotype and clinical behaviour, and prognostic parameters are needed to determine treatment strategies in individual patients. Besides clinical parameters included in the IPI, recent studies have pointed out several biological prognosticators of potential value, such as the percentage of tumour-infiltrating activated cytotoxic T-lymphocytes. The expression of proteins involved in the execution or regulation of apoptosis, such as activated caspase 3, Bcl-2, and PI9, was also found to be strongly related to clinical outcome. These studies indicate that inhibition of the apoptosis cascade in particular is an important mechanism that can explain the poor clinical outcome in therapy refractory ALCL. Functional studies are required to investigate whether disruption of one or more of the apoptosis pathways is the major factor in the fatal outcome of the disease and whether apoptosis resistance based on inhibition of one pathway can be overcome by activating another pathway that is still intact.

Anaplastic Lymphoma Kinase↗

Three novel mutations in the activin receptor-like kinase 1 (ALK-1) gene in hereditary hemorrhagic telangiectasia type 2 in Brazilian patients.

Hereditary hemorrhagic telangiectasia (HHT) or Osler-Rendu-Weber disease is a systemic fibrovascular dysplasia with an autosomal dominant inheritance pattern. Mutations in two genes, endoglin and ALK-1, are known to cause HHT, both of which mediate signaling by transforming growth factor beta ligands in vascular endothelial cells. Ten patients were analyzed. Diagnosis of HHT was carried out by means of family history, recurrent bleeding, and the presence of multiple telangiectases lesions. Conformation-sensitive gel electrophoresis analyses with consistent abnormal migration patterns were cloned and sequenced using the MegaBace 1000 DNA automated analyzer. Three novel mutations were identified in the coding sequence of the ALK-1 gene in five patients and their families, which demonstrated clinical manifestations of HHT type 2. These mutations included a G insertion and a T deletion of single base pairs in exons 3 and 7, as well as missense mutations in exons 7 and 8 of the ALK-1 gene. These data indicate that loss-of-function mutations in a single allele of the ALK1 locus are sufficient to contribute to defects in maintaining endothelial integrity. We suggest the high rate of mutation detection and the small size of the ALK-1 gene make genomic sequencing a viable diagnostic test for HHT2.

Activin Receptors, Type II↗

The bHLH transcription factor Hand is regulated by Alk in the Drosophila embryonic gut.

During embryonic development the midgut visceral muscle is formed by fusion of cells within the visceral mesoderm, a process initiated by the specification of a specialised cell type, the founder cell, within this tissue. Activation of the receptor tyrosine kinase Anaplastic lymphoma kinase (Alk) in the developing visceral muscle of Drosophila melanogaster initiates a signal transduction pathway required for muscle fusion. In this paper, we have investigated downstream components which are regulated by this novel signalling pathway. Here we show that Alk-mediated signal transduction drives the expression of the bHLH transcription factor Hand in vivo. Loss of Alk function results in a complete lack of Hand expression in this tissue, whereas Alk gain of function results in an expansion of Hand expression. Finally, we have investigated the process of muscle fusion in the gut of Hand mutant animals and can find no obvious defects in this process, suggesting that Hand is not critical for visceral muscle fusion per se.

Anaplastic Lymphoma Kinase↗

Truncated ALK derived from chromosomal translocation t(2;5)(p23;q35) binds to the SH3 domain of p85-PI3K.

The chromosomal translocation t(2;5)(p23;q35) is associated with "Anaplastic large cell lymphomas" (ALCL), a Non Hodgkin Lymphoma occurring in childhood. The fusion of the tyrosine kinase gene-ALK (anaplastic lymphoma kinase) on chromosome 2p23 to the NPM (nucleophosmin/B23) gene on chromosome 5q35 results in a 80 kDa chimeric protein, which activates the "survival" kinase PI3K. However, the binding mechanism between truncated ALK and PI3K is poorly understood. Therefore, we attempted to elucidate the molecular interaction between ALK and the regulatory p85 subunit of PI3K. Here we provide evidence that the truncated ALK homodimer binds to the SH3 domain of p85. This finding may be useful for the development of a new target-specific intervention.

Anaplastic Lymphoma Kinase↗

Alternative splicing within the TGF-beta type I receptor gene (ALK-5) generates two major functional isoforms in vascular smooth muscle cells.

We have identified in rat vascular smooth muscle cells (SMCs) the simultaneous expression of two TGF-beta type I receptor (ALK-5) cDNAs, occurring as a consequence of alternate usage of AG splice acceptor motifs separated by 12 nucleotides located at an intron-exon junction. When translated the resultant full length proteins differ from each other only by the in-frame presence or absence of Gly-Pro-Phe-Ser residues adjacent to their transmembrane domain. Stable expression of these alternate ALK-5 isoforms in ALK-5-deficient cells demonstrated that both were competent in signaling TGF-beta-induced growth inhibition and gene transcription, but with an apparently distinct potency. Our data suggest that alternate splicing within the ALK-5 gene is an important mechanism whereby SMCs may regulate their response to TGF-beta.

Activin Receptors, Type I↗

Gas chromatographic determination of S-alk(en)ylcysteine sulfoxides.

A new GC method for determination of S-alk(en)ylcysteine sulfoxides, important secondary metabolites occurring in many plant genera, has been developed. The method is based on isolation of the amino acid fraction by ion-exchange chromatography followed by derivatization with ethyl chloroformate at ambient temperature and reduction of derivatized S-alk(en)ylcysteine sulfoxides by sodium iodide. The main advantages of the new method are its high sensitivity, excellent resolution capability, accuracy and reliability, as well as the possibility to identify unknown compounds by means of GC-MS. The content of alliin and other S-alk(en)ylcysteine sulfoxides was determined in nine different samples of garlic (Allium sativum L.) originating from the Czech Republic, France, and China. The total content of S-alk(en)ylcysteine sulfoxide pool ranged between 0.53 and 1.3% fresh weight, with S-allylcysteine sulfoxide (alliin) being predominant. A novel S-alkylcysteine derivative, S-ethylcysteine sulfoxide (ethiin), not previously reported to occur in Allium species, was found in some of the samples examined.

Chromatography, Gas↗

Bone marrow involvement in NPM-ALK-positive lymphoma: report of two cases.

Two cases of NPM-ALK-positive anaplastic large cell lymphoma (ALCL) with bone marrow involvement are reported. These cases were recognized within a group of NPM-ALK-positive ALCLs (n = 6) by using immunohistochemistry with the ALK1 monoclonal antibody. In case 1, the bone marrow showed diffuse infiltration of round to spindle-shaped lymphoma cells with moderate fibrosis. In case 2, lymphoma cells intermingling with hematopoietic cells could only be identified by immunohistochemical staining. In contrast to the four NPM-ALK-positive ALCL cases, which showed a cohesive growth pattern in the lymph nodes, the two cases reported here displayed lymphoma cells of smaller size, and they were classified as lymphohistiocytic variants histologically. ALK1 stained small-sized components more clearly than did CD30 (HRS-4). These results suggest that bone marrow involvement of NPM-ALK-positive ALCL may be frequently associated with a histological variant showing a small-sized cell component, and that ALK1 immunostaining is a useful tool to investigate lymphomas for bone marrow involvement.

Adolescent↗

Adjuvant alectinib versus chemotherapy in resected ALK-positive non-small-cell lung cancer (ALINA): health-related quality-of-life and safety outcomes from a randomised, open-label, phase 3 trial.

BACKGROUND: For patients with resected, ALK-positive non-small-cell lung cancer (NSCLC), adjuvant alectinib significantly improved disease-free survival versus platinum-based chemotherapy in the global, phase 3, open-label, randomised ALINA trial. We report safety and health-related quality-of-life (HRQoL) outcomes from the ALINA trial. METHODS: Eligible patients aged 18 years or older with resected, ALK-positive, stage IB (&#x2265;4 cm)-IIIA NSCLC (per the American Joint Committee on Cancer and the Union for International Cancer Control Cancer Staging Manual 7th edition) and an Eastern Cooperative Oncology Group performance status of 0-1 were randomly assigned (1:1) via a block-stratified randomisation method to receive oral alectinib (600 mg twice daily) for 24 months or intravenous platinum-based chemotherapy for four 3-week cycles. Randomisation was stratified according to disease stage and race. The primary endpoint, previously reported, was disease-free survival. Safety was a secondary endpoint and HRQoL was an exploratory endpoint. Safety was assessed by the investigator as per the National Cancer Institute Common Terminology Criteria for Adverse Events version 5&#xb7;0 until 28 days after the last alectinib dose or chemotherapy cycle. HRQoL was assessed via the Short-Form 36-item health survey version 2 (SF-36v2) questionnaire at baseline, every 3 weeks to week 12, then every 12 weeks until disease recurrence, consent withdrawal, death, or week 96. Norm-based scoring was applied; clinically meaningful changes were defined using the SF-36v2 manual. Safety was assessed in the safety-evaluable population and HRQoL in the intention-to-treat population. This study is registered with ClinicalTrials.gov (NCT03456076) and is ongoing. FINDINGS: Between Aug 16, 2018, and Dec 8, 2021, 257 patients were assigned to receive alectinib (n=130) or chemotherapy (n=127). 123 (48%) patients were male and 134 (52%) were female; 143 (56%) were Asian. The safety-evaluable population comprised 128 patients who received alectinib and 120 patients who received chemotherapy; median duration of safety follow-up was 24&#xb7;8 months (IQR 22&#xb7;0-24&#xb7;9) in the alectinib group and 3&#xb7;7 months (IQR 3&#xb7;7-3&#xb7;8) in the chemotherapy group. The safety of adjuvant alectinib was generally consistent with its known profile. The most common grade 3-4 adverse events were blood creatine phosphokinase increased (eight [6%] of 128), alanine aminotransferase increased (two [2%] of 128), and blood bilirubin increased (two [2%] of 128) in the alectinib group, and neutrophil count decreased (12 [10%] of 120), neutropenia (ten [8%] of 120), and nausea (five [4%] of 120) in the chemotherapy group. Serious treatment-related adverse events occurred in two (2%; one each with appendicitis and pneumonitis) of 128 patients in the alectinib group and eight (7%) of 120 patients in the chemotherapy group ( most common were gastrointestinal disorders in three [3%] patients). No deaths due to adverse events were reported in either group. There were fewer discontinuations due to adverse events with alectinib (seven [5%]) versus chemotherapy (15 [13%]). A clinically meaningful difference in improvement from baseline was seen at week 12 for bodily pain, role physical, mental health, social functioning, and vitality SF-36v2 domains with alectinib; improvements in physical and mental HRQoL were maintained over 2 years of active treatment (at week 96, mean Mental Component Summary score: 49&#xb7;9 [SD 10&#xb7;4]; mean Physical Component Summary score: 48&#xb7;8 [SD 7&#xb7;2]) and reached levels similar to the general population (population norm: 50). INTERPRETATION: For patients with resected ALK-positive NSCLC, adjuvant alectinib had a manageable safety profile; HRQoL improved and was maintained over 2 years of active treatment. Together with the disease-free survival benefit seen in ALINA, these data support adjuvant alectinib as an important new standard-of-care for patients with resected ALK-positive NSCLC. FUNDING: F&#x2008;Hoffmann-La Roche.

Adult↗

Distribution of S-Alk(en)ylcysteine sulfoxides in some Allium species. Identification Of a new flavor precursor: S-ethylcysteine sulfoxide (Ethiin).

The content of S-alk(en)ylcysteine sulfoxides, important nonvolatile flavor precursors, was determined in 15 different Allium species by means of gas chromatography. The method employed is based on derivatization of S-alk(en)ylcysteine sulfoxides with ethyl chloroformate followed by their reduction with sodium iodide. The total content of S-alk(en)ylcysteine sulfoxides varied considerably in the wide range between 0.02 and 1.3% fresh weight. Not only the total content but also relative proportions of individual derivatives varied to a great extent. A novel S-alkylcysteine derivative, S-ethylcysteine sulfoxide (ethiin), not previously reported to occur in Allium species, was found in most of the samples examined in trace amounts. None of the other S-alk(en)ylcysteine sulfoxides, for example, isopropyl, (Z)-1-propenyl, butyl, or pentyl, were detected in any of the samples analyzed, limiting possible levels of each of these components to </=1 ppm in fresh weight.

Allium↗

High-dose therapy and autologous stem cell transplant does not result in long-term disease-free survival in patients with recurrent chemotherapy-sensitive ALK-negative anaplastic large-cell lymphoma.

Primary systemic anaplastic lymphoma kinase (ALK)-negative anaplastic large-cell lymphoma (ALCL) has a poor prognosis. This study sought to determine if high-dose therapy and ASCT results in long-term disease-free survival (DFS) in patients with recurrent, chemotherapy-sensitive ALK-negative ALCL. All patients with non-Hodgkin's lymphoma (NHL) who underwent ASCT at Wake Forest University and Upstate Medical University from 1 January 1990 to 12 December 2002 were reviewed to determine if they had T-, B- or null-cell NHL that was CD30+/CD15-/ALK negative. In all, 16 patients were thus identified as having ALK-negative ALCL. All 16 patients underwent ASCT at the time of first relapse and form the basis of this report. Median age of the 16 patients was 51 years. There were 11 males and five females. International prognostic index scores in 12 patients at the time of relapse were: low 3, LI 6 and HI 3. Of 15 patients, 13 relapsed after ASCT; one patient was lost to follow-up. Median progression-free survival for the 15 patients was 12 weeks (3-212+ weeks). Of 15 patients, 10 have died; nine of recurrent disease. Median overall survival for the 15 evaluable patients was 72 weeks. In our experience, high-dose therapy and ASCT does not produce long-term DFS in patients with recurrent chemotherapy-sensitive ALK-negative ALCL.

Anaplastic Lymphoma Kinase↗

Disease-associated mutations in conserved residues of ALK-1 kinase domain.

Activin receptor-like kinase-1 (ALK-1), the gene mutated in HHT type 2 (HHT2), is a serine/threonine kinase receptor type I of the TGF-beta superfamily, specifically expressed on endothelial cells. We established an HHT2 genotype in 16 families and report nine novel mutations. These include insertions and deletions of single base pairs in exons 3, 8 and 9, as well as nonsense mutations in exons 4 and 8 of ALK-1, which would lead to premature truncation and unstable mRNA or protein. Three novel missense mutations were identified in exons 7 and 8 of the kinase domain. Five previously reported substitutions were also observed in the families analyzed. Our results bring to 36, the number of mutations associated with HHT2, and are mostly found in exons 8 and 3 followed by exons 4 and 7. To ascertain the potential functional implications of the missense mutations in the ALK-1 kinase domain, we generated a model based on the three-dimensional structure of the homologous ALK-5 kinase domain. Our data reveal that the 11 missense mutations modify residues conserved among type I receptors and alter the polarity, charge, hydrophobicity and/or size of the substituted amino-acid and likely lead to misfolded and nonfunctional proteins.

Activin Receptors, Type I↗

Translocations involving anaplastic lymphoma kinase (ALK).

Anaplastic large-cell lymphoma (ALCL) comprises a group of non-Hodgkin's lymphomas (NHLs) that were first described in 1985 by Stein and co-workers and are characterized by the expression of the CD30/Ki-1 antigen (Stein et al., 1985). Approximately half of these lymphomas are associated with a typical chromosomal translocation, t(2;5)(p23;q35). Much confusion about the exact classification and clinicopathological features of this subgroup of NHL was clarified with the identification of NPM-ALK (nucleophosmin-anaplastic lymphoma kinase) as the oncogene created by the t(2;5) (Morris et al., 1994). With the discovery of NPM-ALK as the specific lymphoma gene mutation, this NHL subtype could be redefined on the molecular level. This achievement was enhanced by the availability of specific antibodies that recognize ALK fusion proteins in paraffin-embedded lymphoma tissues. Several excellent recent reviews have summarized the histopathological and molecular findings of ALCL and their use in the classification of this lymphoma entity (Anagnostopoulos and Stein, 2000; Benharroch et al., 1998; Drexler et al., 2000; Foss et al., 2000; Gogusev and Nezelof, 1998; Kadin and Morris, 1998; Ladanyi, 1997; Morris et al., 2001; Shiota and Mori, 1996; Skinnider et al., 1999; Stein et al., 2000). This review will focus on the molecular function and signal transduction pathways activated by ALK fusion oncogenes, with recent advances and possible clinical implications to be discussed.

Amino Acid Sequence↗

S-alk(en)yl cysteines of garlic inhibit cholesterol synthesis by deactivating HMG-CoA reductase in cultured rat hepatocytes.

The effects of water-soluble organosulfur compounds of garlic on hepatic cholesterol biosynthesis in cultured rat hepatocytes were studied. S-Alk(en)yl cysteines, i.e., S-allyl cysteine (SAC), S-ethyl cysteine (SEC) and S-propyl cysteine (SPC) inhibited cholesterol synthesis from [(14)C]acetate but not from [(14)C]mevalonate. The activity of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase in the cells treated with SAC, SEC and SPC was 30-40% lower than that of the untreated cells. S-Alk(en)yl cysteines did not alter abundance of mRNA coded for HMG-CoA reductase or protein concentration of the enzyme. The ratio of expressed to total activity (E/T) of HMG-CoA reductase was then determined as an index of phosphorylation status of the enzyme. The E/T ratio was reduced 18-29% by SAC, SEC and SPC, resulting primarily from decreased expressed activity. The results suggest that S-alk(en)yl cysteines inhibit cholesterol synthesis by deactivating HMG-CoA reductase via enhanced phosphorylation, but not changing levels of mRNA or the amount of the enzyme. Additionally, of the three S-alk(en)yl cysteines tested, only SAC appears to further decrease the activity of HMG-CoA reductase by increasing sulfhydryl oxidation of the enzyme.

Animals↗

Fusion of a kinase gene, ALK, to a nucleolar protein gene, NPM, in non-Hodgkin's lymphoma.

The 2;5 chromosomal translocation occurs in most anaplastic large-cell non-Hodgkin's lymphomas arising from activated T lymphocytes. This rearrangement was shown to fuse the NPM nucleolar phosphoprotein gene on chromosome 5q35 to a previously unidentified protein tyrosine kinase gene, ALK, on chromosome 2p23. In the predicted hybrid protein, the amino terminus of nucleophosmin (NPM) is linked to the catalytic domain of anaplastic lymphoma kinase (ALK). Expressed in the small intestine, testis, and brain but not in normal lymphoid cells, ALK shows greatest sequence similarity to the insulin receptor subfamily of kinases. Unscheduled expression of the truncated ALK may contribute to malignant transformation in these lymphomas.

Amino Acid Sequence↗

Effects of growth temperature on fatty acid and alk-1-enyl group compositions of Veillonella parvula and Megasphaera elsdenii phospholipids.

Veillonella parvula ATCC 10790, an anaerobic gram-negative coccus, contains diacyl and alk-1-enyl acyl (plasmalogen) forms of phosphatidylethanolamine and phosphatidylserine. We studied the effect of growth temperature on the lipid composition of this strain. There was a small increase in the phosphatidylethanolamine content but no change in the content of plasmalogens at the lower growth temperatures tested. The total acyl chains and the plasmalogen acyl chains contained between 73 and 80% mono-unsaturated fatty acids at all growth temperatures. The plasmalogen alk-1-enyl chains were significantly more unsaturated in cells grown at 30 and 25 degrees C than in cells grown at 37 degrees C. Differential scanning calorimetry of the hydrated phospholipids showed lower phase transition temperatures for the lipids from the cells grown at the lower temperatures. In Megasphaera elsdenii lipids, which are similar in composition to the lipids of V. parvula, the proportion of phosphatidylethanolamine also increased slightly at lower growth temperatures, with no significant change in the content of plasmalogens. M. elsdenii contained cyclopropane fatty acyl and alk-1-enyl chains in addition to the mono-unsaturated and saturated chains previously reported. As cells entered the stationary phase of growth at 30 and 42.5 degrees C, there was a reciprocal increase in the proportion of cyclopropane acyl chains and decrease in the unsaturated moieties. The total proportion of cyclopropane and unsaturated acyl and alk-1-enyl chains was more than 65% at all growth temperatures studied, and there was no discernible increase in the sum of these moieties at the lower growth temperatures.

Fatty Acids↗